• Title, Summary, Keyword: Growth

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Dynamic Study of Tetrahymena pyriformis Growth and Reproduction in Aerobic and Anaerobic Conditions

  • Yoo, Eun-Sun
    • Development and Reproduction
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    • v.15 no.1
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    • pp.9-15
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    • 2011
  • The population growth and reproduction of Tetrahymena pyriformis were studied under shaken (aerobic) and unshaken (anaerobic) conditions by applying the growth models, exponential and logistic growth models and the population growth of Tetrahymena was showed the logistic growth model under both, shaken and unshaken conditions and also, the more oxygenated samples had greater population size (N) and three times faster growth rate (r) than less oxygenated samples during incubation periods.

Seasonal Growth Patterns of Perennial Ryegrass Varieties IV. Growth analysis in spring growth (Perennial Ryegrass 품종의 계절별 생육특성 IIV. 봄철 생육의 생장해석)

  • 김성규;이주삼;조익환
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.12 no.4
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    • pp.226-231
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    • 1992
  • This experiment was carried out to estimate the dry matter accumulation using growth analysis in spring growth of perennial ryegrass varieties grown under space planting conditions, based on the data of previous paper9'. The results obtained were as follows: 1. Growth parameters of leaf area ratio(LAR), specific leaf area(SLA) and leaf weight ratio(LWR) were recognized siginificant differences between varieties. But, specific leaf area(SLA), leaf weight ratio (LWR) and relative tiller appearance rate(RTAR) were recognized significant differences between growth stages. Specific leaf area(SLA) was significant difference for the interaction of variety Xgrowth stage. 2. The relative growth rate of biological yields(BYRGR) indicated significantly positive correlations with relative growth rate of shoot(RGR) and root(RWGR), and net assimilation rate(NAR) as affected by the varieties and growth stages. 3. The relative growth rate of biological yields(BYRGR) indicated significantly positive correlation with nct assimilation rate(NAR) in all varieties. Leaf area ratio(LAR) had significantly positive correlation with specific leaf area(SLA) in all varieties, but shows a significant negative correlation with leaf weight ratio(LWR) of Maprima variety. 4. The relative growth rate of biological yields(BYRGR) indicated significantly positive correlations with the absolute growth rates of yield components.

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Effects of Angelica sinensis Root on Longitudinal Bone Growth Rate in Adolescent Female Rats

  • Lee, Donghun;Kim, Hocheol
    • The Korea Journal of Herbology
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    • v.32 no.1
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    • pp.69-74
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    • 2017
  • Objectives : This study aimed to investigate the effects of Angelicae sinensis Radix on longitudinal bone growth rate in rats. We have screened traditional medicinal herbs to develop the longitudinal bone growth stimulator by well-established rat model. A. sinensis was identified as one of the effective herbs in the screening process. Methods : Adolescent female rats were administered A. sinensis at doses of 30 mg/kg and 300 mg/kg for 10 consecutive days. To observe the rate of longitudinal bone growth, tetracycline was injected intraperitoneally on day 8 to stain a fluorescent band on the anew formed bone. To elucidate the mode of action, we observed insulin-like growth factor-1 (IGF-1) and bone morphogenetic protein-2 (BMP-2) expression after A. sinensis administration in growth plate. Results : In the 300 mg/kg A. sinensis group, the length between the proximal endpoint of the tetracycline label and the division line between growth plate and bone was significantly increased compared with vehicle-treated control group. Height of the proximal tibial growth plate was higher in the A. sinensis group compared with control group. A. sinensis also upregulated the expressions of IGF-1 and BMP-2 in the proliferative zone and hypertrophic zone of the proximal tibial growth plate. Conclusions : A. sinensis increases longitudinal bone growth rate in rats. According to immunohistochemistry, A. sinensis increases local IGF-1 and BMP-2 expressions in the growth plate which can be considered as direct stimulation of GH on the local growth plate.

An Analysis of Crack Growth Rate Due to Variation of Fatigue Crack Growth Resistance (피로균열전파저항의 변동성에 의한 균열전파율의 해석)

  • Kim, Seon-Jin
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.23 no.7
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    • pp.1139-1146
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    • 1999
  • Reliability analysis of structures based on fracture mechanics requires knowledge on statistical characteristics of the parameter C and m in the fatigue crack growth law, $da/dN=C({\Delta}K)^m$. The purpose of the present study is to investigate if it is possible to predict fatigue crack growth rate by only the fluctuation of the parameter C. In this study, Paris-Erdogan law is adopted, where the author treat the parameter C as random and m as constant. The fluctuation of crack growth rate is assumed only due to the parameter C. The growth resistance coefficient of material to fatigue crack growth (Z=1/C) was treated as a spatial stochastic process, which varies randomly on the crack path. The theoretical crack growth rates at various stress intensity factor range are discussed. Constant ${\Delta}K$ fatigue crack growth tests were performed on the structural steel, SM45C. The experimental data were analyzed to determine the autocorrelation function and Weibull distributions of the fatigue crack growth resistance. And also, the effect of the parameter m of Paris' law due to variation of fatigue crack growth resistance was discussed.

Optimal Inflation Threshold and Economic Growth: Ordinal Regression Model Analysis

  • DINH, Doan Van
    • The Journal of Asian Finance, Economics, and Business
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    • v.7 no.5
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    • pp.91-102
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    • 2020
  • The study investigates the relationship between the inflation rate and economic growth to find out the optimal inflation threshold for economic growth. Therefore, this study applied an ordinary least square model (OLS) and the ordinal regression model, and collected the time-series data from 1996 to 2017 to test the relationship between inflation and economic growth in the short-term and long-term. The sample fits the model and is statistically significant. The study showed that 96.6% of correlation between inflation rate and economic growth are close and 4.5% of optimal inflation threshold is appropriate for economic growth. It finds that the optimal inflation threshold is base to perform economic growth, besides the inflation rate is positively related to economic growth. The results support the monetary policy appropriately. This study identifies issues for Government to consider: have a comprehensive solution among macroeconomic policies, monetary policy, fiscal policy and other policies to control and maintain the inflation and stimulate growth; have appropriate policies to regulate inflation to stimulate economic growth over the long term; set a priority goal for sustainable economic growth; not pursue economic growth by maintaining the inflation rate in the long term, but take appropriate measures to stabilize the inflation at the optimal inflation threshold.

The Effect of Professor's Individualized Consideration on the Personal Growth of Chinese Students Study Abroad in Korea: The Moderating Effect of Perceived School Support

  • Hahm, SangWoo;Sun, SiYao
    • International Journal of Advanced Culture Technology
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    • v.8 no.2
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    • pp.76-84
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    • 2020
  • In general, members of an organization want their own growth and development. As these members grow or develop, they feel satisfied and fulfilled in the process. Growth or development can motivate members to become more involved in their jobs. Therefore, these concepts are very important for organizations as well as individual members. Various elements of the organization affect the growth of its members. Leaders influence members to achieve organizational goals. Leaders can therefore be an important variable influencing the growth of members. Specific leadership informally develops the potential to identify and satisfy members' personal needs and to achieve higher performance. These leader behaviors motivate members and drive their growth. Thus, this leadership will have a significant impact on the growth of members. In addition, in this relationship, if members have perceived organizational support, they can further improve their expectations for growth. Therefore, support from leaders and organizations will have a positive impact on employee growth. This study highlights the importance of the growth of members of the organization. It demonstrates the moderating effects of leader's individualized consideration and perceived organizational support necessary elements for member growth. Through this process, the purpose and significance of the study are to identify the variables that affect the personal growth of members and explain how they can grow.

The Comparison of the Physical Characteristics between Boys and Girls at Puberty (사춘기 남녀 청소년의 인체 특징에 관한 비교 - 만 $10{\sim}14$세를 중심으로 -)

  • Jeong, Hwa-Yeon;Kim, Kyung-A;Suh, Mi-A
    • The Research Journal of the Costume Culture
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    • v.15 no.1
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    • pp.37-57
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    • 2007
  • The purpose of this study was to analyze the body measurements of boys and girls at puberty and to provide the fundamental data for pubescent apparel manufacturers to produce clothing that reflect their physical characteristics. A total of 549 boys and 529 girls aged between 10 and 14 were measured in the capital area from March 4 to April 3, 2004. Data were collected from 35 anthropometric items and 12 photographic items per a person. SPSS Ver. 12 program was used in data analysis including means, standard deviation, t-test and Duncan test. The main results of this study were as follows. They showed the significant difference of their growth in accordance with the increase of their ages. There were also the difference between boys and girls. As for height and length items, boys showed a slow growth at the age of $10{\sim}11\;and\;12{\sim}13$. Those at the age of $11{\sim}12\;and\;13{\sim}14$ showed rapid growth. That is, an active growth was followed by a slow growth and that phenomenon repeatedly occurred. On the other hand, girls showed remarkable growth at the age $10{\sim}11$ and the growth rate gradually slowed down afterward. Regarding circumference items, boys at the age of $11{\sim}12\;and\;13{\sim}14$ showed remarkable growth. This results showed that boys at the age of $11{\sim}12$ had vertical growth and horizontal growth at the same time and for those at the age of $13{\sim}14$, growth was more conspicuous in horizontal direction. Meanwhile, for girls, the growth rate was high at the age of $11{\sim}12$, somewhat later than the age of the growth of height and length. As for breadth-related items and depth-related items, for both sexes two items grew steadily throughout the ages, breadth-related items showed a higher growth rate than that of depth-related items. This study analyzed the body measurements of pubescent boys and girls and the results showed that, for boys, an active physical growth took place at the age of 13 according to previous studies, but the findings of this study suggested that the phenomenon now occurred at the age of $11{\sim}12$, which proved that physical growth took place earlier than before. Also, an active growth was followed by a slow growth. Girls at puberty showed remarkable growth of height at the age of $10{\sim}11$ that is consistent with previous studies and then showed horizontal growth at the age of around 12, having a voluminous body shape.

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Effect of Magnetism on the Growth of Several Foliage Plants (몇몇 관엽식물의 생장에 미치는 자기(磁氣)의 영향)

  • Jeong, Seo-Goo;Kim, Sun-Hae;Bang, Kwang-Ja
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.8 no.5
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    • pp.19-27
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    • 2005
  • The earth is a huge magnet. All organisms live under the magnetism of earth. The magnetism influences the ions in the cells of organisms and variously functions to lives as well. The medical treatment with magnet has come down from the ancient, it has an effect on the plants' growth. But there are no scientific studies about the influences of magnetism on plant growth. Accordingly, the experiment about the influence of magnetism on several foliage plants was carried out in this study. The promotion of plants' growth led by magnetism will be the method to save the management cost of horticultural market by early shipment. As a results of this experiment, plants treated with magnets showed excellent growth especially in length growth. The experiment results of the respective plants are the following. 1. Rhapis flabelliformis : This have grown so very well in the container lined with magnets as time goes by. Showing the significant(p<0.05) differences, the length growth of Height and Length of leaves was especially distinguished. 2. Howea belmoreana : This has grown well in all containers. Showing the significant(p<0.05) differences, the length growth of Height and Length of leaves was especially distinguished. 3. Chamaedorea seifrizii : There have been the growth differences between Height and Length of leaves as time goes by. The growth of Height and Length of leaves in the container lined with magnets has been excellent. The number of leaves and number of branch generally had no big differences but the growth of Height and Length of leaves was excellent in the magnet container. The method of plant growth promotion with magnet should save the management cost for this reason. Therefore the succeeding studies about the plant growth under the influence of magnet intensity and kind must be performed. The studies with various plants are needed to activate the program for growing plants with magnet.

Study on the Changes in Enzyme and Insulin-like Growth Factor-1 Concentrations in Blood Serum and Growth Characteristics of Velvet Antler during the Antler Growth Period in Sika Deer (Cervus nippon)

  • Park, Jaehyun;Jeon, Byongtae;Kang, Sungki;Oh, Mirae;Kim, Myonghwa;Jang, Seyoung;Park, Pyojam;Kim, Sangwoo;Moon, Sangho
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.9
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    • pp.1303-1308
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    • 2015
  • This study was conducted to investigate changes in blood enzyme parameters and to evaluate the relationship between insulin-like growth factor-1 (IGF-1), antler growth and body weight during the antler growth of sika deer (Cervus nippon). Serum enzyme activity and IGF-1 concentrations were measured in blood samples collected from the jugular and femoral veins at regular intervals during the antler growth period. Blood samples were taken in the morning from fasted stags (n = 12) which were healthy and showed no clinical signs of disease. Alfalfa was available ad libitum and concentrates were given at 1% of body weight to all stags. The experimental diet was provided at 9 am with water available at all times. There were no significant differences in alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase during antler growth, but alkaline phosphatase concentrations increased with antler growth progression, and the highest alkaline phosphatase concentration was obtained 55 days after antler casting. Serum IGF-1 concentrations measured from blood samples taken from the jugular vein during antler growth, determined that levels of IGF-1 was associated with body weight and antler growth patterns. Serum IGF-1 concentrations were higher at the antler cutting date than other sampling dates. Antler length increased significantly during antler growth (p<0.001), and there was a similar trend to between right and left beams. Body weight increased with antler growth but was not significant. Consequently it appeared that serum alkaline phosphatase concentration was related to antler growth and both antler growth and body weight were associated positively with IGF-1 concentrations during antler growth.