• Journal of The Korean Society of Grassland and Forage Science
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• v.15 no.4
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• pp.238-244
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• 1995

The objective of this study is to obtain the basic data for investigating the effects of organic reserves on winter survial or regrowth yield. Forage rape(Brassica napus L.) was sown on Sep. 1, 1994. Experimental plots were divided into three replicates under 6 different cutting dates(l0 days interval from Oct. 15 to Dec. 4). Field-grown palnts were sampled on the each cutting date and on the wintering period (Jan. 16) to analyze the nitrogen and non-structural cahohydrate reserves. The rate of winter survival and regrowth yield were also measured in the spring of next year. On the before wintering, dry matter yields were 152, 274, 500, 718, 776 and 981 kg/lOa, respectively, from the cutting date on Oct. 15, Oct. 25, Nov. 4, Nov. 14, Nov. 24, and Dec. 4. Cmde protein yield significantly increased as cutting date was later until Nov. 14, thereafter a significant increase did not occured. Nitrogen and starch contents per plant significnatly increased as the cutting date was later. The increasing rate of starch was greatly higher than that of nitrogen. On the wintering period, nitrogen reserves in mts were 85.3, 68.8, 47.6, 28.3, 44.3, and 55.3 mglplant, and starch reserve were 11 1.3, 75.3, 39.3, 19.6, 26.4 and 34.6 mglplant, respectively, in the plots cut on Oct. 15, Oct. 25, Nov. 4, Nov. 14, Nov. 24, and Dec. 4. It showed that carbohydrate reserves were much highly utilized than nitrogen reserves during wintering period. The rates of winter survival were 91, 83, 46, 22, 35 and 43% and regrowth yields were 692, 545, 316, 84, 127 and 140 kgD.M/lOa, respectively, in each plots. The highly significant correlation (p<0.01) between the level of organic reserves and the rate of winter survival or regrowth yield were obtained.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.2
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• pp.205-212
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• 2008

This study aimed to investigate the biofilm formation, bacterial regrowth, and bacterial community structure in the granular-activated carbon (GAC) filter adsorbers (FAs) used in water treatment plants. In 2005 and 2006, raw water, settled water, GAC FA by depth, and filtered water were collected twice a year from water treatment plants (WTPs) B and S. The number of heterotrophic bacteria, including mesophilic and psychrophilic bacteria, in such collected waters was investigated along with the total number of coliforms therein. Heterotrophic bacteria were detected in most samples, mainly at the surface layers of the GAC FAs, and fewer such bacteria were found in the lower and bottom layers. An increase in the bacterial number, however, was observed in the samples from various depths of the GAC FAs in WTPs B and S compared with the surface layers. An increase in the bacterial number was also detected in the filtered water. This may indicate that there is a regrowth of the bacteria in the GAC FA. Considering, however, that heterotrophic bacteria were not found in the filtered water, it can be deduced that most bacteria are removed in the chlorination process. Coliforms were detected at the surface layer of the GAC FAs, but their regrowth was not observed. MicroLog systems were used to identify the bacteria community distribution. Eight genera and 14 species, including Pseudomonas spp., were detected in WTP B, and 8 genera and 9 species, including Aeromonas spp., in WTP S. Further studies are required to elucidate their role in the biofilms in water treatment processes.

• 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.

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.1
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• pp.15-20
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• 2001

Plant growth regulators were treated on the cut perennial ryegrass (Lolium perenne L. cv. Reveille) to investigate the effect on the regrowth after cutting. The growth showed better result when 0.1 or 0.5 mg/L cytokinin were treated. Among cytokinins, kinetin or 2iP gave the better effect on the growth than BAP. In 2.4-D as an auxin. cut plants grew best at the concentration of 0.1 mg/L. The initial regrowth was very vigorous when GA$_3$ was treated as a growth regulator, but the growth was retarded after 2 weeks later of cutting. Co-treatment of kinetin as a cytokinin and 2,4-D as an auxin showed synergistic effect on the regrowth of cut perennial ryegrass. Both plant growth regulators gave the same result at the same concentrations in the suspension culture of perennial ryegrass cells.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.29 no.1
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• pp.65-80
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• 2016

Objective : The purpose of this study is to report the hair regrowth effect of Gagamyeonryunggobon-dan on ICR mice from measuring the change of diverse factors.Methods : Gagamyeonryunggobon-dan was treated by oral administration with 2.5㎎/㎏/day amount for 3 weeks per mouse everyday. Hair regrowth was estimated by change of morphology, angiogenesis, hair follicle activation. The change of morphology was observed with external, internal change and sebaceous gland. Angiogenesis was estimated by image analysis, capillary distribution and angiogenic chemokine(MIP-2). Hair follicle activation was estimated by PCNA, IGF-2 and serotonin.Results : 1. Gagamyeonryunggobon-dan treated group had more and thicker hairs than the group not treated. Especially well developed sebaceous glands were seen in dermis of treated group. 2. Gagamyeonryunggobon-dan treated group had more capillaries near hair follicles of subcutaneous layer and more 2019% MIP-2 positive activity than the group not treated. 3. Gagamyeonryunggobon-dan treated group increased positive activity up to 596% in PCNA, 187% in IGF-2 and 547% in serotonin more than the group not treated.Conclusion : These results shows that Gagamyeonryunggobon-dan have the hair regrowth effect through verifying change of morphology, angiogenesis, chemokines. Consequently Gagamyeonryunggobon-dan is expected to apply to take care of extensive hair loss symptoms.

• Asian Journal of Turfgrass Science
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• v.9 no.1
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• pp.11-42
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• 1995

The investigation was made on the relationship among vegetation, net productivity, regrowth and soils of Moonheri-Wasoori, Soodowon-Sungilkyo and Mt. Kumhak grasslands in Chulwon area. The following conclusions have been made as the results of this study. The vascular flora of the grassland in Moonheri-Wasoori was composed of 102 species, the most of which were Medicago denticulata, Miscanthus sinensis, Arundinella hirta, Festuca ovina and Cassia nomame. The flora of Soodowon-Sungilkyn grassland was composed of 74 species, the most of which were Arundinella hirta, Miscanthus sinensis, Carex nanella, Festuca ovina and Cassia nomame. It of Mt. Kumfiak grassland was composed of 78 species, the most of which were Arundinella hirta, Carex nanella, Festuca ovina, Miscanthus sinensis and Aster scaber. These five species contributed greatly to the standing crop of live material which was in excess of 60% of it. The peak standing crop of each 413.7, 307.6 and $348.7g /m^2$ in Moonheri-Wasoori, Soo- dowon-Sungilkyn and Mt. Kuruhak grasslands wars reached in August under flooded conditions as a result of the growth of dominant species, Medicago denticulata and Arundinella hirta. The net prodution of organic matter was slight in some intervals but occurred throughout the growing season After cutting of grasses, the regrowth of new leaves mainly depended on growing stage and edaphic factors. Characteristics of the natural grassland soils, especially, concerning water, total nitrogen, avail-able phosphorus and exchangeable calcium were clarified and might be depend upon the quantity of plant production. Nitrogen, phosphorus and calcium concentration of leaves of Medicago denticulata, Arundinella hirta and Miscanthus sinensis were higher than of stems. Even if diem we diffurmem in the a-mb of nutrients among Medicago denticulata hirta and Miacanthus sinensis for single species and stands. they were covered by variations within species in the present survey. Key words: Competition, Production, Productivity, Regrowth, Soil Properties, Vascular Flora.

• Journal of Forest and Environmental Science
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• v.37 no.4
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• pp.292-303
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• 2021

Studies that relate the structure of tropical regrowth vegetation to soil properties are generally lacking in the literature. This study proposes three indices for assessing the structural regeneration of secondary forests. They are: (1) the tree diameter class, (2) the plant life form and (3) the woody/herbaceous plants ratio indices. They were applied to assess the regeneration status of forest regrowth vegetation (aged 1-10 years), derived savanna regrowth vegetation in south western Nigeria, and to secondary forests in different stages of succession in Columbia and Venezuela, Bolivia, Mexico in South and Central America and semi-arid savanna in Ethiopia and seasonal deciduous forest successional stages in India. In all the cases, the indices increased with increasing age of regrowth vegetation and hence, with increasing structural complexity of regenerating vegetation. The tree diameter class index increased from 32.1% in a 9-year secondary forest to 69.0% in an 80-year-old secondary forest in Columbia and Venezuela and from 0.4% in a 1-year fallow to 20.9% in 10-year regrowth vegetation in southwestern Nigeria. In semi-arid savanna in northern Ethiopia, the woody/herbaceous plants ratio index increased from 18.1% in a 5-year protected grazing enclosure to 75.1% in 15-year protected enclosure, relative to the status of 20-year enclosure. The indices generally had correlations of 0.6-0.90 with species richness and Simpson's/Margalef's species diversity, implying that they are appropriate measures of ecosystem development over time. The proposed indices also had strong and positive correlations with soil organic carbon and nutrients. They are therefore, significant indicators of fertility status.

• Korean Journal of Plant Resources
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• v.36 no.6
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• pp.571-579
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• 2023

In this study, cryopreservation by droplet-vitrification was applied to pear (Pyrus spp.) germplasm. We focused on the development and assessment of various strategies for the selection of suitable tissue, osmoprotection, and dehydration. We also evaluated post-thaw recovery of cryopreserved explants by droplet-vitrification. Preferentially, we tested the effects of preculture and loading treatments to determine which tissues were more suitable, either the apical shoot tips or the axillary buds. Apical shoot tips showed the better regrowth rate than in vitro axillary buds. The most effective techniques for cryopreservation were as follows. Shoots from in vitro seedlings which had been cultured for about 5-6 weeks were cold-hardened at 4℃ for one week, excised shoot tips were precultured on liquid MS medium including 0.3 M sucrose for 31 hours and 0.7 M sucrose for 17 hours, osmoprotected in loading solution (LS) for 40 min, and then cryoprotected in dehydration solution (PVS3) for 90 min. In addition, we found that regrowth rates of explants on regrowth medium after exposure to liquid nitrogen (LN) were higher than those on MS medium. Results indicated that the highest regrowth percentage was 95.6% for 'Bartlett' cultivar and 68.9% for 'BaeYun No.3' cultivar. Consequently, apical shoot tips of two pear cultivars, 'Bartlett' (P. communis) and 'BaeYun No.3' (P. pyrifolia), were successfully cryopreserved by droplet-vitrification. Results of this study show that the enhanced droplet-vitrification method described in the present study could be used as an effective means for long-term storage of pear genetic resources.

• Journal of Environmental Health Sciences
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• v.32 no.4 s.91
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• pp.282-291
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• 2006

This study investigated the inactivation of the total coliform, an indicator organism in chlorine and chlorine in order to control microbial regrowth for water distribution systems and select an appropriate disinfection strategy for drinking water systems. The disinfection effects of chlorine and chlorine dioxide with regard to the dosage of disinfectant, contact time and DOC was investigated experimentally. In spite of the consistency of chlorine residuals at approximately 0.2 mg/l, bacteria regrowth was detected in the distribution system and it was confirmed by the scanning electron microscope results. The influence of organic carbon change on the killing effect of chlorine dioxide was strong.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.34D no.9
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• pp.64-71
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• 1997

A new etching technique of meltback was investigated for GaAs lensed optical devices with selective windows opending in the LPE (liquid phase epitaxy) system. In the meltback process, the etch depth and the etch shape were controlled by the degree of under-saturation, etch time and other parameters. A GaAs/AlGaAs DH layer was grown on the selectively etched hemispherical well for optical device application such as lensed surface emitting LED. The regrowth process were related with the coolin grate and the well to well spacing. A novel surface emitting LED with hemispherical AlGaAs lens was fabricated using the meltbakc and regrowth as the key process for AlaAs lens array. The light emitting efficiency of the LED was upto three times higher than the similar structure LED without lens. The meltback and regrowth technique was applicable to manufacture the optical device in LPE.