• Title/Summary/Keyword: Order of growth

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Study on the resistance of various herbaceous plants to the effect of heavy metals-responses of plants to soil treated with cadmium and lead- (草本植物의 重金屬 抵抗性에 關한 硏究 - Cadmium, Lead 處理 土壤에 의한 反應 -)

  • Kim, Byung-Woo;Park, Jong-Sun
    • The Korean Journal of Ecology
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    • v.15 no.4
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    • pp.433-449
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    • 1992
  • Three horticultural herbaceous plants and a natural herbaceous plant were tested to determine the growth responses, biomass and uptake of cadmium(cd), lead(pb) by application of cd and pb soil treatment in pot culture. The ecological effects on the growth of the plants were investigated to determine the tolerance for the heavy metal pollutants cd and pb. the marginal concentrain of cd treatment on the growth of the each plant was below the 1, 000 ppm treatment of cd. The marginal concentration of pb treatment was below the 1, 000ppm treatment of pb in cultivation of salvia splendens ker., celosia cristata l. and below the 3, 000ppm treatment of pb in cultivation of portulaca grandiflora hook., sedum saramentosum bunge. the resistance for cd of sedum saramentosum bunge, celosia criastata l., portulaca grandiflora hook. and salvia splendens ker. was in the listed order. The resistence for pb was in order of sedum saramentosum bunge, portulaca grandiflora hook. Salvia splendens ker.and celosia criastata l.stems. The flowering of portulaca grandiflora hook. was sustained in the pb 1, 000ppm treated group only. The higher the concentration of pb in the soil cultivated the plants was, the less the content of leaf chlorophy11 in each plant was. The number of stomata per unit leaf area was the highest in salvia splendens ker. and in order of celosia l., sedum saramentosum bunge., portulaca grandiflora hook., the higher the cd and pb concentration of cd and pb treatment was, the more the concent of cd and pb in the part of each plant increased. the content of cd and pb in the stems of salvia spiendens ker. was the highest in the 1, 000ppm-treated ground and in order of the roots, the leaves and the flowers.

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Perception of Elementary School Teachers about Nutrition Education (초등학교 교사의 영양교육에 대한 인식 조사 연구)

  • 김경애;정난희;오순희
    • Korean Journal of Human Ecology
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    • v.7 no.2
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    • pp.13-30
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    • 2004
  • The purpose of this study was to investigate the status of teacher's perception about the nutrition education of elementary schooL The results of this study were as follows. Most of the teachers responded that nutrition education necessitate in curriculum of elementary school, the main reason for necessity of nutrition education was for proper growth, they thought starting period of nutrition education was to begin when children are in a kindergarten and a infant home. The perception for a suitable person to teach the nutrition education showed dietician, parents, class teacher and a related teacher in oder and the time of that is a related class, as a spare time at everyday, a special activity time, and service a meal in order. Importances of the contents of a nutrition education were proper eating habits, growth and nutrition, a food hygiene and a disease in order. Problems of elementary students' nutrition were a unbalanced eating, a ingestion a processing and instant food too much, lack of table manner, fatness and a weak child in order. The most of expected effects through the nutrition education were a good table habits and manners, the way of a efficient nutrition education were a need of link with parents, a need of link the dietician. a teacher's class and training in order. The average score of nutrition knowledge was 6.3$\sim$6.9 out of 10 and teachers of Gwangju scored more higher on nutrition knowledge than teachers of Jeonnam, as they arranged a dietician was so.

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A Study on Physicochemical Properties of Artificial Substrates and Changes of Plant Growth in Tropical Plant Resources Research Center of Korea National Arboretum (국립수목원 열대온실 내 인공배합토의 물리화학적 특성 및 식물 생육 변화에 관한 연구)

  • Song, Jeong-Hwa;Jin, Hye-Young;Ahn, Tai-Hyeon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.13 no.2
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    • pp.52-62
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    • 2010
  • This study was carried out in the Tropical Plant Resources Research Center of Korea National Arboretum to determine the optimum edaphic environment for the growth of tropical and subtropical plants. The physicochemical properties of artificial substrates and the growth characteristics of tropical and subtropical plants were investigated. Subtropical plants exhibited a high growth rate when cultivated in a substrate of Dry Zone that had physical properties similar to those of arid native soil. Mediterranean plants showed a low growth rate when grown in a substrate of Subtropical Zone that required changes in acidity. The substrate of Tropical Zone had high organic matter and mineral contents and therefore had good physical properties:this substrate has a good environment for the stimulation of the growth of tropical plants. Our results indicate that the chemical properties such as pH and mineral contents of most artificial substrates need to be more urgently improved than their physical properties in order to ensure better growth of tropical and subtropical plants. Initial management strategies for the construction of new tropical greenhouses were formulated, and data from monitoring studies will be continuously gathered and incorporated in the manual to keep it updated.

Effects of the crystal rotation on heat transfer and fluid flow in the modified floating-zone crystal growth (수정된 부유띠결정성장법에서 결정봉의 회전이 유동 및 열전달에 미치는 효과)

  • Seo, Jeong-Se
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.20 no.10
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    • pp.3322-3333
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    • 1996
  • A numerical analysis has been conducted to investigate a modified floating-zone crystal growth process in which most of the melt surface is covered with a heated ring. The crystal rod is not only pulled downward but rotated around its axisymmetric line during crystal growth process in order to produce the flat interface of crystal growth and the single crystal growth of NaNO3 is considered in 6mm diameter. The present study is made from a full-equation-based analysis considering a pulling velocity in all of solid and liquid domains and both of solid-liquid interfaces are tracked simultaneously with a governing equation in each domain. Numerical results are mainly presented for the comparison of the surface shape of rotational crystal rod with that of no-rotational crystal rod and the effects of revolution speeds of the crystal rod. Results show that the rotation of crystal rod produces more its flat surface. In addition, the shape of crystal growth near the centerline is more concaved with the increase in the revolution speed of crystal rod. The flow pattern and temperature distribution is analyzed and presented in each case. As the pulling velocity of crystal rod is increasing, the free surface of the melt below the heated ring is enlarged due to the crystal interface migrating downward.

A Study on the Growth Inhibition of Human Colon Cancer Cells by Eucommial Lea Extract (두충의 인체 암세포 증식억제 효과 연구)

  • 황우익
    • The Korean Journal of Food And Nutrition
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    • v.5 no.1
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    • pp.13-22
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    • 1992
  • This study was divised to observe the inhibitory effect of growth rate of human colon cancer cells by Eucommial leaf extract, in vitro. Three species of human colon cancer cells, HRT-18, HCT-48 and HT-29, were used for the experiment. Each extract of Eucommial leaf was prepared by extraction with water, 95% alcohol, acetone, chloroform and petroleum ether, and then the inhibitory effect of each extract on the growth rate of cells was compared with control group and each other. The experimental results obtained are summarized as follows; 1. Inhibitory effects on growth rate of human colon cancer fells were strongest in the petroleum ether extract and next in the chloroform extract. 2. Inhibitory effects on the growth rate of the cancer cells by extracts of water, 95% alcohol and acetone were weaker than that of petroleum ether and chloroform. 3. Inhibitory effect of each extract on the cancer cell growth was shown most strong activity in HT-29, and was in order of HRT 18 and HCT-48. In view of the results, it could be suggested that inhibitory effects of non-polar solvent's extracts against the cancer cell growth were more stronger than that of polar solvents and the effects were indicated difference according to the species of the cells.

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Associated Bacterial Community Structures with the Growth of the Marine Centric Diatom Cyclotella meneghiniana: Evidence in Culture Stages (해양 원형 규조류 Cyclotella meneghiniana 성장 연관 미생물 군집구조 분석: 배양단계에 따른 증거)

  • Choi, Won-Ji;Park, Bum Soo;Guo, Ruoyu;Ki, Jang-Seu
    • Ocean and Polar Research
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    • v.39 no.4
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    • pp.245-255
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    • 2017
  • There are a number of pieces of evidences that suggest a link between marine diatoms and microorganisms, but knowledge about related microbial communities is greatly lacking. The present study investigated the microbial community structures related to the growth of the marine diatom Cyclotella meneghiniana. We collected free-living bacteria (FLB) and particle-associated bacteria (PAB) at each growth stage (e.g., lag, exponential, stationary and death) of the diatom, and analyzed their bacterial 16S rDNA using pyrosequencing. Metagenomics analysis showed that community structures of FLB and PAB differed considerably with the progress of growth stages. FLB showed higher diversity than PAB, but variation in the different growth stages of C. meneghiniana was more evident in PAB. The proportion of the genus Hoeflea, belonging to the order Rhizobiales, was dominant in both FLB and PAB, and it gradually increased with the growth of C. meneghiniana. However, Enhydrobacter clade tended to considerably decrease in PAB. In addition, Marinobacter decreased steadily in FLB, but first increased and then decreased in PAB. These results suggest that Hoeflea, Enhydrobacter, and Marinobacter may be closely related to the growth of diatom C. meneghiniana.

Fatigue Crack Growth Characteristics of $SiC_p/Al-Si$ Alloy Composites for Automotive Structures (자동차구조용 $SiC_p/Al-Si$복합재의 피로균열 진전특성에 대한 연구)

  • Koh Seungkee;Lee Haemoo
    • Transactions of the Korean Society of Automotive Engineers
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    • v.13 no.4
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    • pp.174-181
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    • 2005
  • In order to investigate the behavior of fatigue crack growth of SiC-particulate- reinforced Al-Si alloy composites, fatigue tests using single edge notched tension(SENT) specimens were performed. Composite materials were manufactured by using both permanent die casting and extrusion processes with different volume fractions of $10\%\;and\;20\%$. $SiC_p-reinfurced$ Al-Si composites showed the increased levels of threshold stress intensity factor range, ${\Delta}K_{th}$, for the increased volume fractions of SiC particles, which implies the increased fatigue crack growth resistance at the threshold or low ${\Delta}K$ levels, compared to the unreinforced Al-Si alloy. In the Paris region, however, the composites showed the increased rate of crack growth resulting in the unfavorable effects on the fatigue crack growth resistance. Critical stress intensity factor range at unstable crack growth leading to final fracture decreased as the volume fraction of SiC particle increased, because of the reduced fracture toughness of the composites. Extruded materials showed higher threshold and critical values than the cast materials.

Effect of Growth Regulators on Growth of Rice Plant I. Effect of Growth Retardants on Growth and Ethylene Evolution of Rice Seedlings (벼 생육에 미치는 생장조정제의 영향 I. 묘의 생육 및 에칠렌생성에 미치는 생장억제제의 영향)

  • Lee, Moon-Hee;Ota, Yasuo
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.30 no.1
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    • pp.101-106
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    • 1985
  • A series of experiments were carried out to know the effect of growth retardants on the growth of rice seedlings and ethylene evolution from the rice seedlings. The results suggested that the reduction rate in order of plant height was S-327 > BAS-106 > NTN-821 > PP-333 > CGR-811. The heigher concentration levels of growth retardants applied. the more effective reductions of plant height were found. Ethylene evolution from the rice seedlings was significantly negative correlated with plant hight of of seedlings in all treatments.

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The Impact of Financial Integration on Economic Growth in Southeast Asia

  • Bong, Angkeara;Premaratne, Gamini
    • The Journal of Asian Finance, Economics and Business
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    • v.6 no.1
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    • pp.107-119
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    • 2019
  • This paper examines the impact of financial integration on economic growth in Southeast Asia over the period 1993-2013. This paper further investigates whether the relationship depends on the level of financial and economic development, government corruption, and macroeconomic policy. These questions raise important issues both from a theoretical and a policy perspective. We employ the generalized methods of moment (GMM) in the dynamic panel estimation framework to analyse several factors, including initial income, initial schooling, financial development, inflation, trade openness, corruption, and financial crisis. The study further analyzes the data using the EGLS model to examine the consistency of the GMM model. We found that financial integration has a significant positive effect on economic growth in Southeast Asia. Our findings suggest that increasing financial integration could improve the productive capacity of the economy, including more investments and efficient allocation of capital, and thus enhancing economic growth in this region. More specifically, the results suggest that the government should work towards eliminating corruption and stabilizing macroeconomics in order to enhance financial integration and economic growth. This paper sheds new insights on a better evaluation of the past and present theorizing on the subject of financial integration and economic growth; especially, in Southeast Asia.

Growth Degree of Quercus Community Plantations for Effective Vegetation Restoration (효과적인 식생복원을 위한 참나무류 군락 식재의 생장량에 관한 연구)

  • Mi-Jin Kim;Eun-Suk Cho;Hee-Jeong Jeong;Dong-gil Cho
    • Journal of Environmental Science International
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    • v.32 no.3
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    • pp.161-171
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    • 2023
  • The present study evaluated growth factors affecting oak community plantations through literature review and a field survey. Specifically, 41 related literature sources were analyzed and field surveys were conducted to collect growth data. Previous studies were analyzed to identify variables with high frequency of use. The frequency of use was in the order of tree size > environment > planting density > forest age. Analysis of factors impacting height and diameter growth revealed that the growth rate of species other than Quercus variabilis was negative in the field survey. This may be because of differences between the actual trees planted and specifications in the construction drawings, which may be attributed to the site conditions and decisions made by the project subject during construction. Furthermore, simple linear regression analysis was conducted with time, height at planting, density, and species code as the independent variables and growth rate as the dependent variable. A strong positive linear correlation was noted between height and diameter. This work builds a foundation for developing a forest restoration model and simulation program based on a regression model derived from the four variables tested.