• Title/Summary/Keyword: growth ages

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A Study of the Influence of Environmental Factors and Factors Associated with Feeding on Infants' Growth (영아의 성장발육에 영향을 미치는 환경요인 및 섭식관련 요인에 관한 연구)

  • 최영선;오기화;양경미;서정숙;신손문
    • Korean Journal of Community Nutrition
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    • v.3 no.1
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    • pp.3-11
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    • 1998
  • This study was aimed to evaluate any influence of environmental factors associated with feeding on infants' growth. One hundred infants(62 males and 38 females) aged 4-9 months were measured for length and were weighed. Their mothers were interviewed using questionnaires including general and environmental characteristics and maternal feeding attitude, ideal body habitus, infant's food behavior, and infant's food behavior, and infant's temperament. A further study was conducted on 29 infants at the time their ages reached 12 months. Their dietary intakes were assessed, and blood hemoglobin and serum ferritin concentrations were measured. Z-scores of weight-for-age(WAZ) and Z-scores of height-for-age(HAZ) of 4-9 month- old infants were not correlated with age, education level, income, weight, and height of their parents. Formula-fed infants had significantly lower WAZ and body mass index (BMI) than those of breast fed infants. WAZ was significantly correlated with maternal feeding attitude, but not with ideal body habitus, infant's food behavior or infant's temperament. WAZ of 12-months after birth because of supplementary foods introduced from 6 months of age. WAZ and BMI were positively correlated with blood hemoglobin concentration. Therefore, to ensure proper growth of infants, efforts should be given to postental factors such as breast-feeding, maternal feeding attitude, adequate iron status as well as prenatal factors. (Korean J Community Nutrition 3(1) : 3∼11, 1998)

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A Growth and Yield Model for Predicting Both Forest Stumpage and Mill Side Manufactured Product Yields and Economics

  • Schultz Emily B.;Matney Thomas G.
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2006.06b
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    • pp.305-309
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    • 2006
  • This paper presents and illustrates the application of a growth and yield model that supports both forest and mill side volume and value estimates. Traditional forest stand growth and yield models represent the forest landowner view of yield and economics. Predicted yields are estimates of what one would expect from a procurement cruise, and current stumpage prices are applied to investigate optimum management strategies. Optimum management regimes and rotation ages obtained from the forest side view are unlikely to be economically optimal when viewed from the mill side. The actual distribution of recoverable manufactured product and its value are highly dependent on mill technologies and configurations. Overcoming this limitation of growth and yield computer models necessitates the ability to predict and price the expected manufactured distribution of lumber, lineal meters of veneer, and tonnes of air dried pulp fiber yield. With these embedded models, users of the yield simulator can evaluate the economics of possible/feasible management regimes from both the forest and mill business sides. The simulator is a forest side model that has been modified to produce estimates of manufactured product yields by embedding models for 1) pulpwood chip size class distribution and pulp yield for any kappa number (Schultz and Matney, 2002), 2) a lumber yield and pricing model based on the Best Opening Face model developed by the USDA Forest Service Forest Products Laboratory (Lewis, 1985a and Lewis, 1985b), and 3) a lineal meter veneer model derived from peeler block tests. While the model is strictly applicable to planted loblolly pine (Pinus taeda L.) on cutover site-prepared land in the United States (US) Gulf South, the model and computer program are adaptable to any region and forest type.

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The relation between serum levels of epidermal growth factor and necrotizing enterocolitis in preterm neonates

  • Ahmed, Heba Mostafa;Kamel, Nsreen Mostafa
    • Clinical and Experimental Pediatrics
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    • v.62 no.8
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    • pp.307-311
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    • 2019
  • Purpose: Necrotizing enterocolitis (NEC) is one of the most serious complications of prematurity. Many risk factors can contribute to the development of NEC. The epidermal growth factor (EGF) plays a major role in intestinal barrier function, increases intestinal enzyme activity, and improves nutrient transport. The aim of this study was to assess the role of epidermal growth factor in the development of NEC in preterm neonates. Methods: In this study, 130 preterm neonates were included and divided into 3 groups, as follows: group 1, 40 preterm neonates with NEC; group 2, 50 preterm neonates with sepsis; and group 3, 40 healthy preterm neonates as controls. The NEC group was then subdivided into medical and surgical NEC subgroups. The serum EGF level was measured using enzyme-linked immunosorbent assay. Results: Serum EGF levels (pg/dL) were significantly lower in the NEC group (median [interquartile range, IQR], 9.6 [2-14]) than in the sepsis (10.1 [8-14]) and control groups (11.2 [8-14], P<0.001), with no significant difference between the sepsis and control groups, and were positively correlated with gestational age (r=0.7, P<0.001). A binary logistic regression test revealed that low EGF levels and gestational ages could significantly predict the development of NEC. The receiver-operating characteristic curve for EGF showed an optimal cutoff value of 8 pg/mL, with 73.3% sensitivity, 98% specificity, and an area under the curve of 0.92. Conclusion: The patients with NEC in this study had significantly lower serum EGF levels (P<0.001), which indicated that EGF could be a reliable marker of NEC in preterm neonates.

Models Describing Growth Characteristics of Holstein Dairy Cows Raised in Korea

  • Vijayakumar, Mayakrishnan;Choy, Yun-Ho;Kim, Tae-Il;Lim, Dong-Hyun;Park, Seong-Min;Alam, Mahboob;Choi, Hee-Chul;Ki, Kwang-Seok;Lee, Hyun-Jeong
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.40 no.3
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    • pp.167-176
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    • 2020
  • The objective of the present study was to determine the best model to describe and quantify the changes in live body weight, height at withers, height at rump, body length and chest girth of Holstein cows raised under Korean feeding conditions for 50 months. The five standard growth models namely polynomial linear regression models, regression of growth variables on the first and second-order of ages in days (model 1) and regression of growth variables on age covariates from first to the third-order (model 2) as well as non-linear models were fitted and evaluated for representing growth pattern of Holstein cows raised in Korean feeding circumstances. Nonlinear models fitted were three exponential growth curve models; Brody, Gompertz, and von Bertalanffy functional models. For this purpose, a total of 22 Holstein cows raised in Korea used in the period from April 2016 to May 2020. Each model fitted to monthly growth curve records of dairy cows by using PROC NLIN procedure in SAS program. On the basis of the results, nonlinear models showed the lower root mean square of error (RMSE) for live body weight, height at withers, height at rump, body length and chest girth (12.22, 1.95, 1.55, 4.04, 2.06) with higher correlation coefficiency (R2) values for live body weight, height at withers, height at rump, body length and chest girth (0.99, 0.99, 0.99, 1.00, 1.00). Overall, the evaluation of the different growth models indicated that the Gompertz model used in the study seemed to be the most appropriate one for standard growth of Holstein cows raised under Korean feeding system.

Growth Analysis of the hard clam, Meretrix petechialis (Lamarck) collected from the Daejuk-ri Shell Middens, Seosan, Korea (서산 대죽리 패총에서 출토된 말백합 Meretrix petechialis (Lamarck)의 성장 연구)

  • Ryu, Dong-Ki;An, Deog-Im
    • The Korean Journal of Malacology
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    • v.29 no.2
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    • pp.121-127
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    • 2013
  • In this study, growth-line analysis was carried out on the hard clam (Meretrix petechialis) collected from the Neolithic shell middens in Daejuk-ri, Seosan, Korea, to reconstruct palaeoenvironment. Growth increments of 206 specimens of the clam were examined. The ages of the specimens were determined from the rings on the shells. The relationship between shell length and ring radius in each ring group was expressed as a regression line, indicating a correspondence in each ring formation. Growth pattern of the midden specimens was compared to that of modern ones collected from Gimje, Jeonbuk. Growth curves for shell length fitted to the von Berta anffy's growth curve were expressed respectively as follows: $SL_t=102.9025[1-e^{-0.18657(t+1.0906)}]$ in the shell midden specimens, $SL_t=104.2583[1-e^{-0.2277(t+0.7499)}]$ in the modern ones. The relationship between shell length (SL; mm) and shell height (SH; mm) was expressed by the following equations: SH = 0.7791 SL + 3.6636 ($R^2$ = 0.946) in the midden specimens, SH = 0.8103 SL + 0.5145 ($R^2$ = 0.991) in the modern ones. The results of the tests regarding the differences between regression coefficients and elevations of growth curves of these two populations demonstrate that the slopes were not significantly different (p < 0.05), but the elevations were (p > 0.05). However, overall growth curves of the midden and modern populations were not significantly different, indicating that shell growth environments of the two areas are similar. Therefore, it is likely that sea temperature near the midden area could be similar to that of present Gimje area, and thus temperature during the period of the midden formation could be higher than presently known.

A Study on Growth Pattern in a New Synthetic Korean Native Commercial Chicken by Sex and Strains (신품종 토종닭의 계통과 성별에 따른 성장 특성에 관한 연구)

  • Kigon, Kim;Eun Sik, Choi;See Hwan, Sohn
    • Korean Journal of Poultry Science
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    • v.49 no.4
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    • pp.229-237
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    • 2022
  • This study investigated the growth characteristics of four strains of newly developed synthetic Korean native commercial chickens (KNCs). We investigated a suitable growth curve model in KNCs and estimated the number of days to reach a 2 kg market weight. Body weight was measured at 2-week intervals from birth to 12 weeks of age. The growth curves were estimated using von Berteralanffy, Gompertz, and logistic functions. The results showed that males were significantly heavier than females at all ages, but there were no significant differences in body weight between strains, except at birth and 2 and 6 weeks of age. The coefficients of determination and adjusted determination of growth function had high goodness-of-fit (97.4~99.7). Of the growth curve parameters, the mature weight and growth ratio were higher in males than in females, but the maturity rate was similar in males and females. The inflection point occurred at approximately 7 weeks of age for females and 8 to 9 weeks of age for males. The weights estimated from the growth curve functions almost agreed with the actual weights, except for male weights estimated using the von Bertalanffy function. The coefficients of determination of the regression equations for weight to age were 0.9583 to 0.9746. The 8- and 10-week-old body weights estimated using the regression equation, and the 12-week-old weight estimated using the logistic function were most similar to the actual weight. Using these models, the estimated age of KNCs to reach 2 kg was 62.0~64.6 days for males and 74.9~78.6 days for females.

Family Selection on Height Growth in Open-Pollinated Progeny Trials of Pinus densiflora Using Relative Height Growth Rate (상대수고생장속도를 이용한 소나무 우수가계 선발)

  • Oh, Chang-Young;Han, Sang-Urk;Lee, Kyung-Joon;Kim, Chang-Soo;Oh, Chan-Jin;Ji, Dong-Hyun
    • Korean Journal of Breeding Science
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    • v.41 no.3
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    • pp.220-227
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    • 2009
  • This study was conducted to select superior families based on the open-pollinated (OP) progeny tests of P. densiflora. A total of 232 OP families were analyzed for relative height growth. The OP progeny test trials were established at 1 to 4 sites from 1975 to 1987. To minimize temporal and spatial variation, we applied the standardization method for family selection. In each progeny test, superior and inferior families were selected at ages of 10, 20 and 30. Relative height growth rate (RHGR), growth speed at a given time unit, was comparatively high at age of 10 with range from 0.1 to 0.6 and showed a large variation among families. However, after age 15, the RHGR was low (average 0.04) and also the variation was not significantly different among families. To reduce selection errors due to age differences (from age 23 to 35) of tests, we made the family selection after age 15 when the values of RHGR were stable. Height growth at each age was transformed to be height growth at age 35 based on the RHGR. As the results, family CB2, CB3, KW99 and KW2 were selected as superior families and KW158, KW22, KB40 and GG1 were considered as inferior ones, respectively. Rank correlations (r) between test ages and selection age 35 were high and statistically significant; r = 0.881 between age 30 and 35, 0.653 between age 20 and 35, and -0.222 between age 10 and 35.

The Growth of Cucumber Seedlings Grown in Paper Pot Trays Affected by Nutrient Management During Seedling Period, Seedling Age, and Night Temperature After Transplanting (종이포트 묘 육묘시 양분관리, 육묘일수 및 정식 후 야온에 따른 오이의 생육)

  • Jang, Yoonah;An, Sewoong;Chun, Hee;Lee, Hee Ju;Wi, Seung Hwan
    • Journal of Bio-Environment Control
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    • v.28 no.4
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    • pp.396-403
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    • 2019
  • This study was conducted to investigate the growth of grafted cucumber seedlings in biodegradable paper pot trays influenced by seedling age, nutrient management before transplanting, and night temperature after transplanting. Grafted cucumber seedlings in paper pot trays were supplied with different nutrient solution concentrations of 0.5 x full strength (S) (EC $0.8dS{\cdot}m^{-1}$), 1.0S(EC $1.6dS{\cdot}m^{-1}$), 2.0S(EC $3.2dS{\cdot}m^{-1}$) two times a week until transplanting. 26, 33, 40, and 47 day-old cucumber grafted seedlings were transplanted and grown at three levels of night temperature (10, 15, and $25^{\circ}C$) during ten days. Increasing nutrient solution concentration enhanced the shoot length, number of leaves, leaf area, dry weight, and relative growth rate of seedlings. With increasing seedling age, the differences in growth were greater among nutrient treatments. The dry matter percentage increased with the seedling age, but was lower with higher nutrient concentration. The specific leaf area showed the opposite results. In cucumbers transplanted at 26- or 33-day seedling ages, night temperature did not affect the growth at ten days after transplanting. However, the growth of 40 or 47 day-old seedling decreased at $10^{\circ}C$. Compared with $25^{\circ}C$, the dry weight of cucumbers transplanted at 40- or 47-day seedling ages was depressed by 58% or 71%, respectively, at $10^{\circ}C$. Accordingly, it was concluded that the optimum nutrient solution concentrations and seedling age for the production of grafted cucumber seedlings in biodegradable paper pot trays can be 1.0S and about 30 days, respectively, and night temperature should be maintained at the range of $15-25^{\circ}C$ for promoting the growth after transplanting.

Variation in Growth Characteristics of Pinus densiflora S. et Z. at Eight Experimental Plantations of Korea (8개(個) 시험지(試驗紙)에서 소나무 산지별(山地別) 생장특성(生長特性) 변이(變異))

  • Kim, Kyu Sick;Han, Young Chang
    • Journal of Korean Society of Forest Science
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    • v.86 no.2
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    • pp.119-127
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    • 1997
  • Japanese red pines growing along the Taebaek mountains have been called "Kangsong" and considered to be superior in growth and wood quality. An attempt was made to determine whether their boundaries for planting may be expanded by testing their early growth at eight experimental plantations of the Republic of Korea. Seeds were collected from the six different natural populations including Uljin in Kyongbuk province. For the provenance test, they were planted in eight different regions including Taean in the spring of 1987. Experimental planting was a randomized complete block design with 3 replications. Height growth was measured at the ages of 2, 4, and 6 after planting, and the diameter at root collar at the age of 6 after planting. Significant variation in height growth was observed among the plantations. The height growth measured at the age of 6 after planting showed a positive correlation with the latitude of the test plantation, and the contents of phosphate, potassium and calcium in the soil. A negative correlation, however, was observed between the longitude of the test plantation and height growth. Ponghwa provenance appeared to be the best among the provenances in that the trees from the area grew 16% better in volume growth than the average of all the trees tested in the study, while the worst one was Kyongju from which trees grew 11% less than the average.

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Health Disparity and Health Welfare among Children from Low-Income Families (저소득 가정 아동의 건강불평등과 건강 복지)

  • Kim, Hee-Soon
    • Child Health Nursing Research
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    • v.19 no.4
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    • pp.247-251
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    • 2013
  • Children from low income families are vulnerable to physical problems including obesity, asthma, hypertension and psychological problems including depression, anxiety. This study was done to identify trends in welfare policy for children from low-income families and future direction for solving health disparity problems. Dream Start is a government-sponsored project that offers services for vulnerable children, ages 0 (include pregnant woman) to 12 years and their families. The Korean Government has made an effort to alleviate health disparity through the 'Health Plan' by establishing health objectives. However, in spite of these efforts by the Korean government, health disparity has worsened in Korea. In order to strengthen family function as well as promote growth and development for vulnerable children, experts in child care need to be significantly involved in identifying neglected children in the community.