• Korean Journal of Environmental Agriculture
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• v.22 no.1
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• pp.36-40
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• 2003

Cyclosulfamuron a herbicide of sulfonylurea type, is a relatively new compound which control broad leaves and perennial weeds in rice field. However, this herbicide has a minor disadvantage of decreasing rice plant growth, especially in early growth stage. Therefore, far introducing this cyclosulfamuron as a herbicide in rice field, it is important to minimize the suppression of early plant growth with maintaining weed control efficacy. This study was conducted to evaluate effects of cyclosulfamuron early plant growth and acetolactate synthase activity of rice (Oryza sativa cv Dongjinbyeo, Hwasungbyeo, Ilpumbyeo). Rice growth was inhibited by cyclosulfamuron in their early growth stage. The concentrations required far 50% inhibition of Dongjinbyeo, Hwasungbyeo and Ilpumbyeo growth were 6.3, 9.2 and 146.mg/kg, respectively. Inhibition effect of cyclosulfamuron on the root elongation was greater than the effect on the shoot growth. Concentrations required far 50% inhibition of acetolactate synthase activity from Dongjinbyeo, Hwasungbyeo, Ilpumbyeo were 42.7, 32.7 and $56.7\;{\mu}M$, respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.10 no.1
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• pp.21-26
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• 1990

This field experiment was carried out to determine the effects of nitrogen(N) application time (March 30, April 9 and April 19) and N fertilizer kind (urea and ammonium sulfate) in early spring on the grass growth, dry matter (DM) yield, crude protein (CP) content, CP yield (CPY), acid detergent fiber (ADF) content, DM digestibility (DMD) and N recovery in orchardgrass (Dactylis glomerata L.) meadow for soiling, 1989. The amount of N applied in early spring was 70 kg $ha^{-1}$, and non-fertilized plot was involved as control. In all fertilized plots the growth, DM yield, CP, CPY and regrowth yield of grasses were significantly increased compared with control. The best grass growth and DM yield were observed on March 30, and the best CP, CPY and N recovery were observed on April 9 among all fertilized plots. Also there were not significant differences between urea and ammonium sulfate fertilizer in grass growth, DM yield, CP, CPY, ADF, DMD and N recovery. In Suwon area, therefore, the optimum time of N application for soiling in early spring may be recommended early April, regardless of fertilizer kind of N.

• Journal of Nutrition and Health
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• v.31 no.1
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• pp.5-12
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• 1998

This study was designed to examine how dietary protein levels affect organ growth and protein metabolism in early and normally weaned rats. Early and normally weaned rats separated fro the dam on the 15th and 121st day postpartum, respectively. were fed diets containing three levels of protein : low(10%) , normal (20%),and high(40%) . On the 35th day, the weight and DNA, RNA and protein contents in brain , liver, and kidney were determined to ascertain organ and cellular growth. Furthermore, serum total protein , albumin , $\alpha$-amino N and creatine and urinary urea N, and creatinine were determined in order to ascertain protein metabolism and renal functions. Dietary protein levels were not observed to significantly affect total DNA content, which may represent an index of cell number in the liver, brain and kidney. Fresh weight and protein/DNA ratio, which may represent indices of cell size, significantly increased in proportion to dietary protein in the kidney. As for the early weaned rats , the liver cell size significantly decreased. Dietary protein levels and weaning periods did not affect serum total protein and albumin . However, serum urea-N significantly increased in proportion to dietary protein levels whereas serum $\alpha$-amino N was decreased by early weaning . Nitrogen retention was lower in early weaned rats fed low or high levels of protein than in normally weaned rats. The results demonstrate that low or high levels of dietary protein have less desirable effects on protein metabolism in prematurely weaned rats.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.1
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• pp.44-47
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• 2000

Cell growth and DNA synthesis were studied from a cultured early- and late- pas- sage mouse aorta smooth muscle cell (MASMC) because the proliferation of vascular smooth muscle cell (VSMC) is a key factor in development of atherosclerosis. In this study, the cells were cultured in fetal bovine serum (FBS) and stimulated by growth factors such as thrombin and platelet-derived growth factor-BB (PDGF-BB). Compared to the number of early-passage MASMC (passage 3 to 9) the number of late-passage MASMC (passage 30 to 40) in a normal serum state was increased 2 fold at Day 1, 3 and 6 in culture, respectively. Incorporation of $[^3H]$ thymidine into DNA induced by serum, PDGF and thrombin in late-passage MASMC was greater than those in early-passage MASMC. We also examined whether intracellular zinc levels would be an aging factor or not. The intracellular zinc level in early- and late-passage MASMC was monitored by using the zinc probe dye N-(6-methoxy-8-quinolyl)-p-toluenesulfonamide. It is interested that late-passage MASMC increased the intracellular fluorescence level of zinc, more than the early passage MASMC did. The alterations of intracellular zinc level occur concurrently with changes in MASMC proliferation rate during aging. This data suggest that the age-associated changes in zinc concentrations may provide a new in vitro model for the study of smooth muscle cell differentiation.

• Korean Journal of Environmental Agriculture
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• v.19 no.2
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• pp.142-146
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• 2000

To observe the stimulating effects of low dose ${\gamma}-radiation$ on the seed germination, early growth and physiological activity in the gourd, seeds of three cultivars (Partner, Support, FR Yongja) were irradiated at the dose of $0.5{\sim}30\;Gy$. The hormetic effects of the low dose ${\gamma}-radiation$ on the growth were different from each cultivar. Low dose ${\gamma}-radiation$ had promoting effects on the germination at the optimum dose of 2 Gy and 8 Gy and on the early growth at the optimum dose of 4 Gy, 16 Gy and 20 Gy in Partner and Support cultivar and 1 Gy in FR Yongja cultivar. Irradiation didn't have significant effects on the chlorophyll contents of gourd plantlet. The antioxidant enzyme activity of gourd plantlet and early growth increased in low dose irradiation group.

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.4
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• pp.324-330
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• 1994

The objective of this study is to obtain the basic data for investigating the potentiality of continuous utili~ation (first cutting in the late fall and regrowth yield in next spring) of forage rape seeded in fall. Fresh yield and the content of nitrogenous compound in leaves and roots were measured during a growth period. Fresh yield accumulation was very low between the late fall(470kg/10a) and the early regrowth period( 1.070kg /IOa). Total nitrogen content in leaves until the wintering period was decreased from 4.71% to 3.70%. while that in roots slightly increased during this period. The highest content(4.84%) in roots was observed in the early regrowth period, and then rapidly decreased as growth advanced. Protein-N was the largest pool of nitrogenous compound in leaves and roots through entire growth period, Its content in leaves decreased until the wintering period (Feb. 4), and then increased until the bolting stage(Apr. 10). Protein-N in roots highly accumulated from the late fall(11.1mg/gDM) to the early regrowth period(l6.9mg/gDM), and then decreased until the early tlowering stage. The content of amino acid-N in leaves showed a little change with a range from 5.7 to 8.5mgIgDM during entire growth period, while that in roots rapidly decreased from early regrowth period. The content of $NO_3$-N decreased from 7.0 to 4.3mglgDM in leaves, while increased from 0.9 to 2.3mg/gDM in roots from the late fall to the wintering period. 7he content of $NH_4$-N was lower and less varillble than other nitrogen compound during entire growth period. The results clearly showed that protein-N was the main storage form and highly accumulated in roots of overwintering forage rape.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.7
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• pp.1722-1729
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• 1994

At early stage of creep-fatigue crack growth tests, initial transient behavior which implies high crack growth rate has been generally observed by some researchers. Since the influence of the initial transient crack growth behavior on the remaining life of components is significant, cause of it should be further studied. In this study, characteristics of the initial transient behavior of 1Cr-1Mo-0.25V steel is studied experimentally by performing creep-fatigue crack growth tests at $538^{\circ}C$ in air under trapezoidal waveshapes. It is verified that the cause of the initial transient behavior is not high ${(C_t)}_{avg}$ values due to the small scale creep condition at the early stage of test, but oxidation-dominated crack growth mechanism during the transient period which is different from the creep-dominated crack growth mechanism in steady crack growth period.

• The Korean Journal of Ecology
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• v.13 no.3
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• pp.225-236
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• 1990

We studied that seeds of wild radish with different size of weight can be obtained for the purpose of differentiation and growth of these seeds by total growth periods. This study is practised a view of plant eco-physiological side and dry-matter production. Through whole growth periods, we knowthat seed weight of L plots was higher than that of M and S plots. In the 33th day after day after germination, growth values of L, M and S plots were 13.93, 7.77, and 4.61 g/plant, respectively. Growth of shoot (cotyledon and leaf) area and shoot weight were shown the similar trends with individual plant dry-amtter weight. In the 33th day after germination, shoot area of L, M and S plots were 21.55, 11.81 and 8.75 $cm^3$/plant and shoot dry weight of L, M and S plots were 10.83, 6.03, 3.50 g/plant, respectively. In the early stage of growth (the 10-14th day after germination), the values of RGR of seed weight of L, M, S plots were 0.2887, 0.2807 and 0.2365 g/g/day, in the late stage of growth, those values of RGR of L, M, S plote were 0.2721, 0.1716, 0.1727 g/g/day, respectively. In the early stage of growth (the 14th day after germination), the values of NAR or L, M and S plots were 0.1513, 0.1373, and 0.1094 g/$cm^2$/day, respectively. It is thought that seed weights were influenced seriously effect in the early stage of growth. The NAR value, in the late stage of growth (the-28-33th day after germination), of L, M and S plots were not large different as 0.1086, 0.1097 and 0.112 g/$cm^2$/day, respectively. The LAR values of M and S (2.0396, 2.1520 $m^2$/g) plots, in the early stage of growth, were higher than L (1.9037 $m^2$/g) plots. In the late stage of growth, the value of LAR of L plots were nearly same as M plots, but the value of S plots were higher than that of L and M plots (0.0458 $m^2$/g). And, in the early stage of growth, the values of SLA of L, M and S plots were 2.2123, 2.2107 and 2.8448 $m^2$/g, respectively. We measured the photosynthetic rates and the respiratory rates as the physiological characteristics of wild radish. In the early stage of growth, the photosynthetic rates of L, M and S plots were 12.4, 14.4, 9.8 $\mu$mol /$m^2$/sec and 9.4, 11.4, 9.8 $\mu$mol/$m^2$ /sec in the late stage of growth, respectively. In this result, it could be informed that photosynthetic rates in the late stage of growth were lower than the early stage. In the middle stage of growth, the respiratory rates were 0.793, $\mu$mol/$m^2$/min in shoot, and 3.28 $\mu$mol/$m^2$/min in root without relation to seed weight. The growth analysis of plants was used by Hunt & Parson s computer program (1974, 1981) and its results used this program were good. Therefore, in this sense, it could be expected that the computer program used and developed largely in researches of plant growth.

• Journal of The Korean Society of Grassland and Forage Science
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• v.11 no.3
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• pp.153-157
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• 1991

The present study eluciciated the effect of water holding matter on emergence and survival of forage grasses in seedling and early growth stage. Vermiculite was used as u7ater holding matter. Experiment was conducted with 2 treatments, soil only and soil with 3% vermiculite. The results obtained were as follows: Most of character related to emergence and early growth were improved clearly by adding vermiculite. Specially, root growth was increased when vermiculite was added in soil. Survival percent at drought stress condition was also improved by adding vermiculite. Rut the amount of water keeping by verm~culite was not much.

• BMB Reports
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• v.41 no.5
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• pp.363-368
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• 2008

Two genes of temperate mycobacteriophage L5, namely, gp63 and gp64, were hypothesized to be toxic to M. smegmatis. An identical L5 gp64 ortholog (designated hlg1) was cloned from homoimmune mycobacteriophage L1 and characterized at length here. As expected, hlg1 affected the growth of M. smegmatis when overexpressed from a resident plasmid. HLG1 (the protein encoded by hlg1) in fact caused growth retardation of M. smegmatis and the region encompassing its 57-114 C-terminal amino acid residues was found indispensable for its growthretardation activity. Both nucleic acid and protein biosynthesis were severely impaired in M. smegmatis expressing HLG1. Interestingly, HLG1 also affected E. coli almost similarly. This putative delayed early lipoprotein did not participate in the lytic growth of L1.