• Title/Summary/Keyword: regrowth rate

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Relationship between Specific Stubie Weight and Regrowth of Perennial Ryegrass (Perennial ryegrass의 그루터기 면적중과 재생과의 관계)

  • 이주삼;김성규
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.11 no.2
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    • pp.90-96
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    • 1991
  • This experiment was carried out in order to estimate the recovery days of root and stubble to the days after cutting, and contribution of specific stubble weight on the regrowth was examined using the relationships between the dry weight of shoot and yield components, and regrowth parameters by the days after cutting. The varieties examined were Maprima, Manhattan, Tove, Peramo, Caliente, Tempo and P-2 grown under individual plant basis. The results are may be summarized as follows: 1. Dry weight of root and stubble were recovered up to 13.5 and 11 days after cutting, respectively. 2. Dry weight of shoot(regrowth parts+stubble) was affected significantly by the varieties, stages of regrowth and variety x stage of regrowth. 3. The variety with tiller weight type showed higher average productivity of shoot than those of the variety with tiller number type. 4. Absolute growth rate(AGR) of shoot was correlated significantly with regrowth parts, stubble, root and weight of a tiller at the early stage of regrowth(up to 12 days after cutting), and correlated with regrowth parts, stubble, weight of tiller and stubble area at the late stage of regrowth(up to 20 days after cutting). 5. Contribution of specific stubble weight to absolute growth rate of shoot was different between the stages of regrowth. Thus, regrowth parts per specific stubble weight(RP1SSbW) and weight of tiller per specific stubble weight(WT1SSbW) contributed to absolute growth rate of shoot at the early stage of regrowth, and efficiency of specific stubble weight(ESSbW), regrowth parts per specific stubble weight (RPISSbW) and weight of a tiller per specific stubble weight(WT1SSbW) contributed to absolute growth rate of shoot at the late stage of regrowth. 6. Regrowth utilization rate(RUR) was one of the useful regrowth parameter to indicate the regrowth potential of grasses.

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Assessment of the Bacterial Regrowth Potential in Drinking Water System Using Specific Regrowth Rate (재증식속도에 의한 상수도 시스템의 세균재증식능 평가)

  • Oh, Jung-Woo
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.3
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    • pp.309-315
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    • 2005
  • In this study, the bacterial regrowth characteristics in drinking water were investigated for various nutrient concentrations and forms using improved BRP method as a traditional approach and specific regrowth rate as a new index. The results of bacterial regrowth potential for glucose and $NH_4^+-N$, which was evaluated by BRP method as a traditional index, appeared to be higher relative to that of acetate or humic acids as carbon source and $NO_2^--N\;or\;NO_3^--N$ as nitrogen sources, respectively. The results obtained by specific regrowth rate as a new index were similar to that of BRP method with respect to the nutrient conditions examined in this study; i.e., the specific regrowth rate for glucose(ranged from 0.005 to $0.082\;hr^{-1}$) was feater than that acetate and humic acids(ranged from 0.005 to $0.068\;hr^{-1}$ and from 0.005 to $0.008\;hr^{-1}$, respectively). And specific regrowth rate for $NH_4^+-N$ (ranged from 0.008 to $0.072\;hr^{-1}$) was feater than that $NO_2^--N\;and\;NO_3^--N$ (ranged from 0.008 to $0.055\;hr^{-1}$ and from 0.008 to $0.059\;hr^{-1}$, respectively). Therefore, specific regrowth rate can be applied in order to evaluate the bacterial regrowth potential in drinking water.

Twelve-Month Volume Reduction Ratio Predicts Regrowth and Time to Regrowth in Thyroid Nodules Submitted to Laser Ablation: A 5-Year Follow-Up Retrospective Study

  • Roberto Negro;Gabriele Greco;Maurilio Deandrea;Matteo Rucco;Pierpaolo Trimboli
    • Korean Journal of Radiology
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    • v.21 no.6
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    • pp.764-772
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    • 2020
  • Objective: Laser ablation is a therapeutic modality used to reduce the volume of large benign thyroid nodules. Unsatisfactory reduction and regrowth are observed in some treated nodules. The aim of the study was to evaluate the long-term outcomes of laser treatment for solid nodules during a 5-year follow-up period, the regrowth rate, and the predictive risk factors of nodule regrowth. Materials and Methods: We retrospectively evaluated patients with benign, solid, cold thyroid nodules who underwent laser ablation and were followed-up for 5 years. According to the selection criteria, 104 patients were included (median baseline nodule volume, 12.5 mL [25.0-75.0%, 8-18 mL]; median energy delivered, 481.5 J/mL [25.0-75.0%, 370-620 J/mL]). Nodule volume, thyroid function test results, and ultrasound were evaluated at baseline and then annually after the procedure. Results: Of 104 patients, 31 patients (29.8%) had a 12-month volume reduction ratio (VRR) < 50.0% and 39 (37.5%) experienced nodule regrowth. Of these 39 patients, 17 (43.6%) underwent surgery and 14 (35.9%) underwent a second laser treatment. The rate of nodule regrowth was inversely related to the 12-month VRR, i.e., the lower the 12-month VRR, the higher the risk of regrowth (p < 0.001). The mean time for nodule regrowth was 33.5 ± 16.6 months. The 12-month VRR was directly related to time to regrowth, i.e., the lower the 12-month VRR, the shorter the time to regrowth (p < 0.001; R2 = 0.3516). Non-spongiform composition increased the risk of regrowth with an odds ratio of 4.3 (95% confidence interval [CI] 1.8-10.2; p < 0.001); 12-month VRR < 50.0% increased the risk of regrowth with an odds ratio of 11.7 (95% CI 4.2-32.2; p < 0.001). Conclusion: The VRR of thyroid nodules subjected to similar amounts of laser energy varies widely and depends on the nodule composition; non-spongiform nodules are reduced to a lesser extent and regrow more frequently than spongiform nodules. A 12-month VRR < 50.0% is a predictive risk factor for regrowth and correlates with the time to regrowth.

A study of Solid Phase Epitaxial Regrowth of Silicon using Laser Interferometry (Laser Interferometry를 이용한 Solid Phase Epitaxial Regrowth에 관한 연구)

  • Park, Se-Geun;Walser, R.M.
    • Proceedings of the KIEE Conference
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    • 1987.07a
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    • pp.532-535
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    • 1987
  • A laser interferometry of very high spatial resolution was built to study the solid phase epitaxial regrowth of furnace-annealed silicon wafers. As boron concentration increases up to $1.0E20/cm^3$, regrowth rate increases, but pre-exponential term and activation energy are decreased.

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Biochemical Changes of Dissimilation and Assimitation in Zoysia japonica Steud during the Regrowth Process after mowing (한국잔디(Zoysia japonica Steud.)의 예초후 재생과정에 따른 이화적, 동화적 생화학변화에 관한 연구)

  • 장남기;김형기;유준희;김용진;임채성
    • Asian Journal of Turfgrass Science
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    • v.1 no.1
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    • pp.56-68
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    • 1987
  • During the regrowth the process after mowing, NRA in the leaf was the highest activity from the 5th day to the 7th day. Before mowing, the NRA in the root was not almost detected. But, the NRA in root appeared a rapid increasing activity from the 3rd day to the 4th day after mowing ( Figs.27 ~ 32). During the regrowth process after mowing, a general tendency of AA in the aboveground parts appeared an increasing tendency from the 1st day to the 4th day, a rapid increasing tendency from the 7th day to the 8th day reaching its peak, and a decreasing rate on the 8th and 9th day reaching its peak, and a decreasing rate on the 8th and 9th day. But the AA in the root appeared rapid increasing rate from the 2nd day to the 7th day, the heginning of reagrowth, this tendency showed a similar figure in the case of Total Soluble Carbohydrate ( TSC) in the internode. Both AA and NRA were appeared recovery stage frorn the 8th day after mowing(Figs.15~20). During the regrowth process after mowing, changes of the maximum plant lengths were 18.27cm in the 6cm mowing plot on the 24th day after mowing, 18.83cm in the 3cm mowing plot on the 18th day after mowing, and 18.16cm in the 6cm mowing plot on the 14th day after mowing ( Fig.2). During the regrowth process after mowing. changes in Dry Matter (DM) contents in leaf and stem were a slow decreasing tendency from the 1st day to the 4th day. From the 5th day to the 8th day it appeared a rapid increasing tendency. And afterward until the 15th day. All treatments were reached at a steady state ( Figs.3 ~ 8). During the regrowth process after mowing, changes in the TSC contents of stem and crown were a slow decreasing tendency from the 1st day to the 5-6th day. Prom the 7th to the 8th day three was a rapid increasing tendency. And afterward until the 15th day there was a decreasing rate at a steadyv state. In root there was a similar tendency to that of leaf and stem organs. A general tendency in internode, the TSC content appeared a similar figure to increment of AA (Figs. 9 - 14). During the regrowth process after mowing, changes in te Crude Proem (CP) content of ahoveground parts appeared a slow increasing tendency from the 1st day to the 5-6th day, where it is peak. And afterward to the 15th day there was a decreasing rate at a steady state. But, in toot there were a contrary tendency to that of aboveground

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Analysis of Data Spectral Regrowth from Nonlinear Amplification

  • Amoroso, Frank;Monzingo, Robert A.
    • Journal of Communications and Networks
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    • v.1 no.2
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    • pp.81-85
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    • 1999
  • The regrowth of OQPSK power spectral sidelobes from AM/AM and AM/PM amplifier nonlinearity is analyzed. The time-domain expression for amplifier output shows how spectral re-growth will depend on the cubic coefficient of the Taylor's series of the amplifier nonlinearity as well as input amplitude ripple. Closed form spectrum calculations show that the spectral sidelobes produced by AM/PM take the same form as those produced by AM/AM. The rate of growth of AM/PM sidelobes is, however, not as great as for AM/AM.

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Study on Improvement of Etch Rate and SiO2 Regrowth in High Selectivity Phosphoric Acid Process (고선택비 인산공정에서의 식각율 향상과 SiO2 재성장에 관한 연구)

  • Lee, Seunghoon;Mo, Sungwon;Lee, Yangho;Bae, JeongHyun
    • Korean Journal of Materials Research
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    • v.28 no.12
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    • pp.709-713
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    • 2018
  • To improve the etch rate of $Si_3N_4$ thin film, $H_2SiF_6$ is added to increase etching rate by more than two times. $SiO_3H_2$ is gradually added to obtain a selectivity of 170: 1 at 600 ppm. Moreover, when $SiO_3H_2$ is added, the etching rate of the $SiO_2$ thin film increases in proportion to the radius of the wafer. In $Si_3N_4$ thin film, there is no difference in the etching rate according to the position. However, in the $SiO_2$ thin film, the etching rate increases in proportion to the radius. At the center of the wafer, the re-growth phenomenon is confirmed at a specific concentration or above. The difference in etch rates of $SiO_2$ thin films and the reason for regrowth at these positions are interpreted as the result of the flow rate of the chemical solution replaced with fresh solution.

Effect of Cutting Height on C and N Reserves and Consequent Regrowth in Frequently Defoliated Turf-Type Perennial Ryegrass(Lolium perenne L.) (잔디형 페레니얼 라이그라스에서 잦은 예취조건하의 예취높이가 저장 탄수화물과 단백질 함량 및 재생에 미치는 영향)

  • 김대현;정우진;이복례;김길용;김태환
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.21 no.2
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    • pp.89-96
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    • 2001
  • Carbohydrate and soluble protein reserves and regrowth characteristics in response to cutting height were investigated over four regrowth cycles of turf-type perennial ryegrass(Lolium perenne L. cv. preludeII). When the plants were at the full-vegetative stage (twelve weeks-old), three sequential defoliations at 3, 6 and 9 cm above the root base were imposed at 2-week intervals. Shoot dry weight in all three treatments continuously decreased with progressing regrowth cycle and the decreasing rate was higher as cutting height was lowered. TNC (total non-structural carbohydrate) in stubble at the end of the fourth regrowth cycle in 3, 6 and 9 cm cutting height decreased by 98%, 82% and 27%, respectively, comparing the initial content. TNC in roots also largely decreased with similar pattern in response to cutting height, whereas the absolute amount was much less compared to stubble. Soluble protein in stubble in 3, 6 and 9 cm cutting height decreased by 98%, 82% and 57%, respectively, at the end of fourth regrowth. A significant correlations between TNC (r=0.906) or protein (r=0.879) at the fourth defoliation and dry weight of regrowing shoots at the end of fourth regrowth were observed. these results indicated that cutting height closely influences the levels of organic reserves available for new growth, and that the levels of reserves might provide a useful tool as a determinant for regrowth dynamics.

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( Partitioning of Carbon and Nitrogen Reserves During Winter Adaptation and Spring Regrowth III. Effect of cutting date on the content of organic reserves on the wintering period and forage yeild in rape( Brassica napus L. ) (저장탄수화물과 질소의 월동성과 재생활력에 대한 이용성 III. 추파 유채 ( Brassica napus L. ) 의 예취기시가 월동중 저장유기물 함량 및 수량에 미치는 영향)

  • 김태환;김기원;정우진;전해열;김병호
    • 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.

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Effect of Bensulfuron-methyl on Bud Sprout and Regrowth from Growth Cessation in Eleocharis kuroguwai (올방개 괴경(塊莖)의 맹아(萌芽)와 재생후(再生後) 생육(生育)에 미치는 Bensulfuron-methyl 의 영향(影響))

  • Shin, H.S.;Chun, J.C.;Lee, C.K.
    • Korean Journal of Weed Science
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    • v.12 no.1
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    • pp.1-7
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    • 1992
  • The experiment was conducted to investigate effects of bensulfuron-methyl{methyl 2-((((((4,6-dimethoxypyrimidin-2-yl)amino)carbony)amino)sulfonyl)methyl)benzoate}on bud sprouting, percent regrowth, and regrowth from growth cessation in Eleocharis kuroguwai. Application of bensulfuron-methyl resulted in sprouts of two of three lateral buds in addition to the apical bud of E. kuroguwai. With bensulfuron-methyl the culms elongated from the sprouted buds were killed soon after emergence. However, the buds remained biologically active. During the period of growth cessation the tuber buds respired in a minimum rate, but respiration began to increase with regrowth. At regrowth increase in the respiration was greater in the lateral buds than in the apical bud. Days required to regrowth was 35 days in the suppressed apical bud when applied at the rate of 51 g a. i. ha bensulfuron-methyl, while the suppressed lateral buds sprouted first and second required 29 and 28 dyas, respectively. After regrowth number of new culms was two to three times greater in the lateral buds than in the apical bud.

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