• Title/Summary/Keyword: growth rates

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Effects of Temperature and Light Intensity on the Gametophyte Fragment Growth of Ecklonia cava Kjellman (Laminariales, Phaeophyta) (대형 갈조류 감태(Ecklonia cava Kjellman) 배우체 단편의 생장에 미치는 온도와 조도의 영향)

  • Kang, Jin Woo;Chung, Ik Kyo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.48 no.5
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    • pp.704-711
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    • 2015
  • We examined the effects of temperature and light intensity on gametophyte growth of Ecklonia cava Kjellman. The growth of female and male gametophytes was investigated before maturation. Gametophytes prepared from Munseom, Jeju, Korea in October 2014 were separated by sex and maintained under the following conditions: 15℃, 20 μmol·m-2·s-1, and a 12-h/12-h light/dark cycle. The experiments were conducted at five temperatures (10, 15, 20, 25, and 30℃) and three light intensities (5, 20, and 40 μmol·m-2·s-1). Daily growth rates were estimated by the increase in filamentous frond area. The optimal growth conditions for female gametophytes were 20℃ and 40 μmol·m-2·s-1; the optimal conditions for male gametophytes were 15℃ and 20 μmol·m-2·s-1. The relative growth rates (RGR) of female and male gametophytes decreased at 25℃ and 30℃, respectively. At 30℃, RGRs of gametophytes decreased by approximately 1.0% day-1. In addition, RGRs of male gametophytes were higher than those of female gametophytes. These results indicate that female gametophytes were more sensitive to temperature and light intensity than male gametophytes. Moreover, these results suggest that E. cava growth rates could decrease as a result of global warming.

SERIAL INVESTIGATION ON THE INTERRELATIONSHIP BETWEEN BODY HEIGHT, WEIGHT AND SELECTED CRANIOFACIAL DIMENSIONS DURING MIXED DENTITION PERIOD (혼합치열기 학동에서 신장 및 체중과 두개안면부사이의 상호관계에 관한 연구)

  • Sung, Jae Hyun
    • The korean journal of orthodontics
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    • v.10 no.1
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    • pp.81-93
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    • 1980
  • The interrelationships between growth rates (and size) of the selected cranifacial dimensions and body dimensions (height and weight) were investigated in the longitudinal data of primary school children from 6 to 11 years of age. The data were obtained from serial cephalometric radiographs and health record which were taken at one year interval. Regression analyses were used to analyze the data. The main concludions might be summarized as follows; 1. Size relationships between body height (and weigh) and S-Gn, posterior facial height (s-Go), total mandibular length (Ar-Gn) showed high significant correlation, but no association between body height, weight and anterior cranial base length (S-N). 2. Correlation coefficients between facial dimensions and body height (and weight) were getting lower with age increase. 3. At all age groups, significant prediction equation for some facial dimensions with body height and weight were obtained. 4. In this sample, the growth rates of facial dimensions and body height and weight showed almostly constant during this age period and the growth rate of body height and weight of girls was exceeded that of boys. 5. A relatively high degree of variation between individuals existed in the sample. 6. A positive correlation was found for the relationship between the growth rates of facial dimensions and those of body height (and weight) in boys and girls, but was not found in total samples.

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Spatial Heterogeneity and Long-term Changes in Bivalve Anadara broughtoni Population: Influence of River Run-off and Fishery

  • Silina, Alla V.
    • Ocean Science Journal
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    • v.41 no.4
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    • pp.211-219
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    • 2006
  • A comparison was made of population of the economically important cockle Anadara (=Scapharca) broughtoni (Bivalvia, Arcidae) inhabiting different areas of the Razdolnaya River estuary at the head of Amurskii Bay (Peter the Great Gulf, East Sea). Also, changes in cockle population density and structure, as well as in cockle growth rates during the last 20 years were studied. In all years of investigation, the morphometrical parameters and growth rates of cockles were smaller at the sites located close to the River mouth than farther down-estuary. The differences can be attributed to higher concentration of suspended particulate matter, decreased salinity and water temperature, as well as a longer exposure to these unfavorable environmental factors at sites located close to the River mouth, compared to farther sites. For two decades, cockle population density had decreased by almost 30 times at some sites in the River estuary. The main reason for this population decline is commercial over-fishing of the cockle. Besides, for the last 20 years, linear parameters of the cockles in the population decreased approximately by 30% and weight parameters, almost two times. Cockle growth rates also decreased for this period. Evidently, these facts are due to the damaging effect of dredging.

Effect of Ambient Gas to Growth of SiO2 Nanowires by Vapor Evaporation Method (기상휘발법에 의한 이산화규소 나노와이어의 성장에 미치는 가스의 영향)

  • Rho Dae-Ho;Kim Jae-Soo;Byun Dong-Jin;Lee Jae-Hoon;Yang Jae-Woong;Kim Na-Ri
    • Korean Journal of Materials Research
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    • v.15 no.5
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    • pp.323-333
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    • 2005
  • Effects of gases to growth of $SiO_2$ nanowires were characterized. $N_2$, Ar, and $O_2$ gas's effect were determined. $SiO_2$ nanowires growth scheme was varied by kind and flow rates of gases because of amounts of $O_2$. Flow rates of gases and kind of substrates affected nanowires' diameters, lengths and morphologies of grown nano wires. With increasing flow rates of gases, nanowire's diameter increased because of additional VS and SLS reactions. By TEM characterization, We knows that, grown $SiO_2$ nanowires on Si substrate showed two shell structures. These shapes of nanowires were formed by reaction of additional SLS growth. Grown $SiO_2$ nanowires showed blue luminescence by PL characterization These Blue luminescence was due to quantum confinement effect and oxygen vacancies in the nanowires.

Effects of an Infant Care Education Program for Mothers of Late-preterm Infants on Parenting Confidence, Breastfeeding Rates, and Infants' Growth and Readmission Rates

  • Jang, Eun Hye;Ju, Hyeon Ok
    • Child Health Nursing Research
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    • v.26 no.1
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    • pp.11-22
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    • 2020
  • Purpose: The purpose of this study was to evaluate the effects of an education program for mothers of late-preterm infants on parenting confidence, breastfeeding rate, and infants' growth and readmission rate. Methods: The participants were 53 mothers of late-preterm infants (26 in the experimental group and 27 in the control group). The experimental group was administered the late-preterm care education program while the control group received standard care. The program consisted of two sessions during hospitalization after birth, one session at the time of discharge, and telephone and social networking service consultations at weekly intervals for the month following discharge. The collected data were analyzed using the t-test, x2 test, and repeated-measures analysis of variance. Results: Parenting confidence and the breastfeeding rate were significantly higher in the experimental group than in the control group. However, there was no significant difference in the late-preterm infants' growth and readmission rates between the experimental and control groups. Conclusion: A care education program for mothers of late-preterm infants can be a useful nursing intervention in clinical practice.

Effect of Specimen Thickness on Fatigue Crack Growth (피로균열진전에 미치는 시편 두께의 영향)

  • 김재훈;김영균;윤인수
    • Journal of the Korean Society of Safety
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    • v.13 no.4
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    • pp.79-86
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    • 1998
  • The effect of specimen thickness on fatigue crack growth behavior has been carried out by compact tension specimens of thickness of 3mm, 10mm and 25mm for maraging steel and Al 7075-T6. The closure points were determined during the test by means of a clip-gage situated at the notch mouth. Specimen thickness have no apparent influence on the fatigue crack growth rate of maraging steel, but the crack growth rate of 25mm thickness specimen for Al 7075-T6 is faster than that of 3 and 10mm specimens. The difference of crack growth rates can be successfully explained by considering the different stress state of plane strain and plain stress due to the variation of specimen thickness. Also the crack opening ratio of 25mm specimen is greater than those of 3 and 10mm specimens. When a side groove is introduced in a 10mm specimen, the crack growth rate is approximately similar to that of 25mm specimen. The effective thickness expression of $B_e=B_o-(B_o-B_N)^2B_o$ is the most appropriate to evaluate the crack growth rate of side-grooved specimen. Fatigue crack growth rates can be well described by $\Delta K_{eff}$ of the crack closure points in regardless of all thickness and side-grooved specimens.

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Effects of Various Intensities and Wavelengths of Light Emitting Diodes (LEDs) on the Growth of the Prasinophytes Tetraselmis suecica and T. tetrathele (담녹조강 Tetraselmis suecica 및 Tetraselmis tetrathele의 생장에 미치는 발광다이오드(Light-Emitting Diodes; LEDs) 광량과 파장의 영향)

  • Han, Kyong Ha;Oh, Seok Jin
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.51 no.1
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    • pp.64-71
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    • 2018
  • This study was conducted to investigate the effects of light intensity and wavelength on the growth of Tetraselmis suecica and Tetraselmis tetrathele. These species were exposed to a blue light-emitting diode (LED; max=450 nm), a yellow LED (max=590 nm), a red LED (max=630 nm) and a fluorescent lamp (three wavelengths). The maximum growth rates (${\mu}_{max}$) of T. suecica and T. tetrathele under a red LED were 1.12/day and 0.95/day, respectively. Under a yellow LED, growth rates were 70% of the values for red wavelength, with low half-saturation constants (Ks). The optimum light source to ensure economically effective and productive growth in a Tetraselmis culture system (Photo-Bioreactor) would thus appear to be a three-phase culture, wherein a yellow LED is used during the lag phase and initial exponential phase to increase growth rate, followed by a red LED during the middle exponential phase to maximize growth rate, and finally a yellow LED again during the late exponential phase and stationary phase to achieve increased yield of useful bioactive substances.

Modeling Age-specific Cancer Incidences Using Logistic Growth Equations: Implications for Data Collection

  • Shen, Xing-Rong;Feng, Rui;Chai, Jing;Cheng, Jing;Wang, De-Bin
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.22
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    • pp.9731-9737
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    • 2014
  • Large scale secular registry or surveillance systems have been accumulating vast data that allow mathematical modeling of cancer incidence and mortality rates. Most contemporary models in this regard use time series and APC (age-period-cohort) methods and focus primarily on predicting or analyzing cancer epidemiology with little attention being paid to implications for designing cancer registry, surveillance or evaluation initiatives. This research models age-specific cancer incidence rates using logistic growth equations and explores their performance under different scenarios of data completeness in the hope of deriving clues for reshaping relevant data collection. The study used China Cancer Registry Report 2012 as the data source. It employed 3-parameter logistic growth equations and modeled the age-specific incidence rates of all and the top 10 cancers presented in the registry report. The study performed 3 types of modeling, namely full age-span by fitting, multiple 5-year-segment fitting and single-segment fitting. Measurement of model performance adopted adjusted goodness of fit that combines sum of squred residuals and relative errors. Both model simulation and performance evalation utilized self-developed algorithms programed using C# languade and MS Visual Studio 2008. For models built upon full age-span data, predicted age-specific cancer incidence rates fitted very well with observed values for most (except cervical and breast) cancers with estimated goodness of fit (Rs) being over 0.96. When a given cancer is concerned, the R valuae of the logistic growth model derived using observed data from urban residents was greater than or at least equal to that of the same model built on data from rural people. For models based on multiple-5-year-segment data, the Rs remained fairly high (over 0.89) until 3-fourths of the data segments were excluded. For models using a fixed length single-segment of observed data, the older the age covered by the corresponding data segment, the higher the resulting Rs. Logistic growth models describe age-specific incidence rates perfectly for most cancers and may be used to inform data collection for purposes of monitoring and analyzing cancer epidemic. Helped by appropriate logistic growth equations, the work vomume of contemporary data collection, e.g., cancer registry and surveilance systems, may be reduced substantially.

Study on Spawning Induction and Larvae Breeding of the Hard Clam, Meretrix petechiails (Lamarck) (말백합, Meretrix petechiails (Lamarck) 의 산란유발 및 유생사육에 관한 연구)

  • Kim, Byeong-Hak;Moon, Tae-Seok;Park, Ki-Yeol;Jo, Pil-Gue;Kim, Min-Chul
    • The Korean Journal of Malacology
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    • v.26 no.2
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    • pp.151-156
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    • 2010
  • For industrialization of the hard clams, Meretrix petechiails (Lamarck), spawning was induced per spawning induction technique in the artificial maturation group administered of parent maturation control and the natural maturation group of which parents were transported for artificial spawning per time period. Then, fertilization rates, hatching rates and D-shaped larva development rates were investigated. In addition, growth and survival rates of larvae were investigated per larva breeding technique. The results of spawning induction by exposure in the artificial maturation group indicated that response rates were relatively higher at 23% and 32% respectively at the 4th hour and the 8th hour of exposure. In terms of water temperature increase, responses began only when the temperature reached $28^{\circ}C$ or higher. In the experiment group administered with both exposure and water temperature increase techniques, response rate was found to be 45% or higher at the 4th hour of exposure and the temperature of $28^{\circ}C$. At the temperatures of 29, 30 and $31^{\circ}C$, significant differences were not observed. Therefore, it was indicated that the response rates of parent hard clams were higher toward water temperature increase than exposure time. As for spawning induction per time period of the transported parent group, response rate and D-shaped larva development rate were the highest at 67.6% and 96% respectively on August 6, 2009. In terms of water temperatures during larva breeding experiment, growth was faster as water temperature was higher. In addition, growth and survival rates were relatively higher at the salinity of 25. In terms of stocking density, growth and survival rates were relatively higher at 5 inds./mL.

Development of computer program for the Growth Function in plant Growth Analysis: Effect of Seed Weight and Resources on Growth of Wild Radish (Raphanus raphanistrum) (植物의 成長과 成長解析에 對한 Computer Program 開發에 關한 硏究 - 種子의 무게, 資源이 植物의 成長에 미치는 影響)

  • Choe, Hyun Sup
    • 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.

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