• Title/Summary/Keyword: growth ratio

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Effects of Varying Nutritional and Cultural Conditions on Growth of the Ectomycorrhizal Fungus Pisolithus tinctorius SMF

  • Suh, Hyung-Won;Don L. Crawford
    • Journal of Microbiology and Biotechnology
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    • v.1 no.2
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    • pp.121-125
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    • 1991
  • The culture conditions and nutritional requirements for enhanced mycelial growth of the ectomycorrhizal fungus P. tinctorius SMF were determined in flask scale experiments. Optimum culture conditions for growth of P. tinctorius SMF in a further modified Melin-Norkrans broth were as follows; temperature 25~$27^{\circ}C$, agitation 120 rpm, and pH 4.0. P. tinctorius SMF utilized various carbon sources including monosaccharides, disaccharides, and polysaccharides. D-Glucose and mannitol were respectively the first and second most suitable carbon sources for mycelial growth. With D-Glucose as the principal carbon source, supplementation of modified Melin-Norkrans (MMN) broth with Lysine (800 mg/l), Glutamic Acid (500 mg/l), or Proline (50 mg/l) enhanced mycelial yields 63%, 34%, and 22% respectively as compared to growth in medium lacking amino acids. ThiaminㆍHCl+biotin+pyridoxine supplementation also enhanced growth. As compared to mycelial growth in the MMN medium, growth of P. tinctorius SMF was enhanced 120% in MMN broth when the carbon/nitrogen ratio was 25/1 in citrate buffer at pH 4.5, and growth was 50% greater in MMN broth of carbon/nitrogen ratio with a 10/1~20/1 without using the buffer. Standard conditions established for growth of P. tinctorius SMF in MMN broth were 25~$27^{\circ}C$, agitation 120 rpm, buffered to pH 4.0 with citrate, in MMN medium containing 10 g/l D-glucose supplemented with 800 mg/l lysine. In this medium the carbon/nitrogen ratio was 20/1~25/1, and the maximal mycelial yield ($Y_{x/s}$ ) was 0.472 (4.72 mg/ml) after 7 days of incubation, as compared to 0.214 (2.14 mg/ml), when the fungus was grown in standard MMN broth.

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Comparison of Yield and Growth Characteristics of Korean High Yielding Cultivars and IRRI's New Plant Type Rice Line

  • Lee, Byun-Woo;Ha, Jong-Ryuk
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.44 no.1
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    • pp.59-63
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    • 1999
  • Yield and growth characteristics were compared for five rice cultivars; a new Tongil-type, so called "super-rice", Dasanbyeo, an old Tongil-type Milyang 23, two japonicas Dongjinbyeo and Ilpumbyeo, and a new plant type (NPT)line IR65600-27-1-2. The objective of this stusy was to clarify the high yielding capacity of Dasanbyeo in terms of growth characteristics. The average grain yield (9 t/ha) of Dasanbyeo was higher than that of Milyang 23 by ca. 9% that of japonicas by 20 to 30%, and that of NPT line by ca. 100%. The higher grain yield of Dasanbyeo was attributable not only to the greater dry matter production but also to the higher harvest index (HI). Dasanbyeo showed the greatest dry matter at harvest owing not only to the rapid leaf expan-sion at early growth stage and the resulting high LAI through the entire growth stage but also to the high NAR despite the high LAI. The rapid leaf expansion of Dasanbyeo at early growth stage seemed to be related in part to the profuse tillering capacity. HI was 0.53 in Dasanbyeo, 0,51 in Milyang 23, 0.41 in japonicas, and 0.35 in NPT line. Dasanbyeo was indebted for its higher HI to the relatively high grain filling ratio in spite of a much greater sink size than the other cultivars. Dasan had a greater source to sink ratio during grain ripening as measured by LAD/spikelet and dry matter production/spikelet which showed positove correlations with the grain ripening ratio. New plant type (NPT) line showed the lowest grain yield owing to the small sink size and the low grain filling ratio which seemed to have resulted from the abundant occurrence of weak-strength spikelets. The weak sink strength, in turn, seemed to have suppressed photosynthesis during the grain ripening stage.

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A Study on the Fatigue Crack Growth threshold Characteristic for Steel of Pressure Vessel at Low Temperature (압력용기용강의 저온피로 크랙전락 하한계 특성에 관한 연구)

  • 박경동;하경준
    • Proceedings of the KWS Conference
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    • 2001.05a
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    • pp.224-227
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    • 2001
  • In this study, CT specimens were prepared hem ASTM SA516 which was used for pressure vessel plates for room and low temperature service. And we got the following characteristics from fatigue crack growth test carried out in the environment of room and low temperature at $25^{\circ}C$, -3$0^{\circ}C$, -6$0^{\circ}C$, -8$0^{\circ}C$, -l$0^{\circ}C$ and -l2$0^{\circ}C$ and in the range of stress ratio of 0.1, 0.3 by means of opening mode displacement. At the constant stress ratio, the threshold stress intensity factor range $\Delta K_{th}$ in the early stage of fatigue crack growth ( Region I ) and stress intensity factor range $\Delta$K in the stable of fatigue crack growth ( Region II) was increased in proportion to descend temperature. It assumed that the fatigue resistance characteristics and fracture strength at low temperature is considerable higher than that of room temperature in the early stage and stable of fatigue crack growth region. The straight line slope relation of logarithm da/dN - $\Delta$K in Region II, that is, the fatigue crack growth exponent m increased with descending temperature at the constant stress ratio. It assumed that the fatigue crack growth rate da/dN is rapid in proportion to descend temperature in Region H and the cryogenic-brittleness greatly affect a material with decreasing temperature.

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Crack Propagation Behavior for Variable Load in Cantilever Beam under Bending Load (굽힘하중의 받는 외팔보의 변동하중에 대한 균열진전 거동)

  • 김엽래
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1998.03a
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    • pp.178-183
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    • 1998
  • This paper examines the crack growth behavior of 7075-T651 and 5052-H32 aluminum alloys for variable load within tensile load range condition. The cantilever beam type specimen with a chevron notch is used in this study. The crack growth and closure are investgated by compliance method. The applied initial stress ratio is R=0.3 and variable load are R=0.65, 0.46. Crack length, stress intensity factor range, ratio of effective stress intensity factor range and crack growth rate etc. are inspected with fracture mechanics estimate.

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Effects of dietary fat saturation level on growth performance, carcass traits, blood lipid parameters, tissue fatty acid composition and meat quality of finishing pigs

  • Chen, Jing;Li, Jiantao;Liu, Xianjun;He, Yang
    • Animal Bioscience
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    • v.34 no.5
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    • pp.895-903
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    • 2021
  • Objective: The objective of this study was to investigate the effects of various dietary unsaturated to saturated fatty acids ratios (UFA to SFA ratios) on growth performance, carcass traits, blood lipid parameters, tissue fatty acid (FA) composition, and meat quality of finishing pigs. Methods: A total of 45 crossbred pigs ([Duroc×Landrace]×Yorkshire), with an average initial body weight of 60.3±2.4 kg, were randomly allocated to three treatment groups of 1:1, 2:1, and 3:1 dietary UFA to SFA ratios. Results: Both average daily gain and average daily feed intake of pigs were decreased linearly (p<0.05), whereas backfat thickness was decreased linearly (p<0.05) with increasing of dietary UFA to SFA ratio. Serum triglyceride and low density lipoprotein cholesterol were decreased quadratically or linearly (p<0.05) respectively, whereas high density lipoprotein cholesterol was increased quadratically (p<0.05) with increasing dietary UFA to SFA ratio. In M. longissimus thoracis, the proportion of C18:1 and monounsaturated FA was decreased linearly (p<0.05), whereas the proportion of C18:2n-6, C20:4n-6 and polyunsaturated FA (PUFA) were increased linearly (p<0.05) as dietary UFA to SFA ratio increased. In the subcutaneous adipose tissue, the proportion of SFA was decreased linearly (p<0.05), whereas the proportion of n-6 PUFA, n-3 PUFA, and the UFA to SFA ratios were increased linearly (p<0.05) with increasing of dietary UFA to SFA ratio. Meat color scores and shear force of pigs were decreased linearly (p<0.05), whereas drip loss and cooking loss were increased linearly (p<0.05) with increasing of dietary UFA to SFA ratio. Conclusion: Appropriately boosted dietary UFA to SFA ratio could be conductive to optimize blood lipid parameters and tissue FA composition. However, when the ratio is too high or too low it tends to have negative effects on growth performance and meat quality.

The Effect of Stress Ratio on Fatigue Crack Propagation Rate in SA516/70 Pressure Vessel Steel at Low Temperature (SA516/70 압력용기 강의 저온 피로균열 진전 속도에 미치는 응력비의 영향)

  • 박경동;김정호;최병국;임만배
    • Journal of the Korean Society of Safety
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    • v.16 no.1
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    • pp.18-24
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    • 2001
  • The fatigue crack growth behavior of the SA516/70 steel which is used for pressure vessels was examined experimentally at room temperature, $-60^{\circ}C$,$-80^{\circ}C$ and $-100^{\circ}C$ with stress ratio of R=0.05, 0.1 and 0.3. Fatigue crack propagation rate da/dN related with stress intensity factor range ${\Delta}K$ was influenced by stress ratio in stable of fatigue crack growth (Region II) with an increase in ${\Delta}K$. The resistance of fatigue crack growth at low temperature is higher compared with that at room temperature, which is attributed to the extent of plasticity-induced by compressive residual stress according to the cyclic loads. Fractographic examinations reveal that the differences of the fatigue crack growth characteristics between room and low temperatures are mainly explained by the crack closure and the strengthening due to the plasticity induced and roughness induced.

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A Study on Marketing Strategic Types and Performance in the Korea Apparel Firms

  • Chun Tae-Yoo
    • International Journal of Costume and Fashion
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    • v.5 no.1
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    • pp.75-89
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    • 2005
  • The purpose of this study is to empirically ascertain how the fitness between marketing strategy each firm chooses and environment facing each firm affects the performance of firms measured by the growth rate of market share and the growth rate of profit/sales ratio. In doing so, firms are divided into three groups. With regard to the marketing strategy, firms are classified into three groups based on marketing strategy type; prospector, analyzer, and defender. The main result of this study are as follows: First, responding firms are classified into prospector, analyzer, and defender following Miles & Snow's marketing strategy types. This classification is made using a self typing method and further confirmed by a factor analysis using a number of variables relating marketing objectives and marketing mix. Second, the results show that there are significant differences across marketing strategies in the performance measures of the growth rate of market share and profit/sales ratio. It seems, however, that there is no straight forward relationship between the marketing strategy and the performance measures. This strongly implies that the type of marketing strategy to be adopted by each firm should depend on the environment facing each firm. Third, the result indicates that the growth rate of market share tends to depend only on the marketing strategy type regardless of sufficiency and variation of environment, but profit/sales ratio tends to depend on the fitness between marketing strategy type and environment. It implies that a firm should adopt different marketing strategies for different environment characteristics, in order to enhance the efficiency of resources used reflected in the profit/sales ratio.

PERFORMANCE OF RAINBOW TROUT (Oncorhynchus mykiss) FED ON DIFFERENT DIETARY PROTEIN WITH FIXED ENERGY RATIO

  • Mahmud, S.;Chakraborty, S.C.;Das, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.9 no.1
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    • pp.31-35
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    • 1996
  • An experiment was conducted on rainbow trout(Oncorhynclus mykiss) for eight weeks to investigate the growth performance of the fish fed with different dietary protein with constant diet energy of $20kJg^{-1}$. Four diets containing 25, 30, 35 and 40% crude protein were used. The highest mean final weight was obtained for the fish fed with diet having 35% protein. Growth performance in terms of Specific Growth Rate (SGR), Food Conversion Ratio (FCR) and Protein Efficiency Ratio (PER) were calculated for each diet. There were no significant differences in SGR but the highest value was exhibited by fish fed with 35% protein diet. Significant differences were found among FCR of different diets. Diets with 35 and 40% crude protein gave better FCR value than that of 25 and 30% crude protein. Although significant differences were not found between PER of different diets but PER of diet with 35% protein was found to be better than PER of both high and low protein diets (diets of 40 and 30% crude protein). It is concluded that diet having 35% protein with protein energy ratio of $17.53mgkJ^{-1}$ was suitable for rainbow trout (O. mykiss) among the protein spectrum used.

The Effect of Stress Ratio on Fatigue Crack Propagation Rate in SA516/60 Pressure Vessel Steel at Low Temperature (저온 압력용기용 SA516/60강의 피로균열 진전 속도에 미치는 응력비의 영향)

  • 박경동;하경준;박상오
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2001.11a
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    • pp.80-87
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    • 2001
  • The fatigue crack growth behavior of the SA516/60 steel which is used for pressure vessels was examined experimentally at room temperature $25^{\circ}C, -30^{\circ}C, -60^{\circ}C, -80^{\circ}C, -100^{\circ}C$ and -l2$0^{\circ}C$ with stress ratio of R=0.05, 0.1 and 0.3. Fatigue crack propagation rate da/dN related with stress intensity factor range ΔK was influenced by stress ratio in stable of fatigue crack growth (Region II) with an increase in ΔK. The resistance of fatigue crack growth at low temperature is higher compared with that at room temperature, which is attributed to the extent of plasticity-induced by compressive residual stress according to the cyclic loads. Fractographic examinations reveal that the differences of the fatigue crack growth characteristics between room and low temperatures are mainly explained by the crack closure and the strengthening due to the plasticity induced and roughness induced.

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Cynanchum wilfordii and Phlomis umbrosa Extract (IPLUS-CWPU) Stimulated Bone Growth and Differentiation by Enhancing Growth-Related Factors in Young Sprague Dawley Rats

  • Song, Hye-Jin;Seo, Yoonhee;Hong, Sang Keun;Choe, Soo Young
    • The Korean Journal of Food And Nutrition
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    • v.34 no.6
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    • pp.568-575
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    • 2021
  • The purpose of this study was to investigate the effects of extract mixture of C. wilfordii and P. umbrosa (IPLUS-CWPU) on bone growth in 4-week old young male SD rats. To confirm the effect of IPLUS-CWPU, we measured the length of bone growth plate, the ratio of proliferative zone to the length of growth plate and the expression level of insulin-like growth factor, IGF-1. The IPLUS-CWPU treatment shows a significant increase of tibial and femoral growth plate and the ratio of proliferative zone in growth plate. Especially, the length increased by 13.9% and 25.3% in the tibia and femur, respectively, in the high-dose group compared to the normal group. Moreover, the expression of IGF-1 gene in liver was upregulated in IPLUS-CWPU treated groups. These results indicated that IPLUS-CWPU administration could increase the proliferative zone of bone growth plate in early developmental stage by upregulation of IGF-1 gene.