• Communications for Statistical Applications and Methods
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• v.29 no.1
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• pp.65-83
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• 2022

Although various statistical methods have been developed to map time-dependent genetic factors, most identified genetic variants can explain only a small portion of the estimated genetic variation in longitudinal traits. Gene-gene and gene-time/environment interactions are known to be important putative sources of the missing heritability. However, mapping epistatic gene-gene interactions is extremely difficult due to the very large parameter spaces for models containing such interactions. In this paper, we develop a Gaussian process (GP) based nonparametric Bayesian variable selection method for longitudinal data. It maps multiple genetic markers without restricting to pairwise interactions. Rather than modeling each main and interaction term explicitly, the GP model measures the importance of each marker, regardless of whether it is mostly due to a main effect or some interaction effect(s), via an unspecified function. To improve the flexibility of the GP model, we propose a novel grid-based method for the within-subject dependence structure. The proposed method can accurately approximate complex covariance structures. The dimension of the covariance matrix depends only on the number of fixed grid points although each subject may have different numbers of measurements at different time points. The deviance information criterion (DIC) and the Bayesian predictive information criterion (BPIC) are proposed for selecting an optimal number of grid points. To efficiently draw posterior samples, we combine a hybrid Monte Carlo method with a partially collapsed Gibbs (PCG) sampler. We apply the proposed GP model to a mouse dataset on age-related body weight.

• The Korea Journal of Herbology
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• v.29 no.5
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• pp.31-38
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• 2014

Objectives : Egg yolk is composed of various important chemical substances for human health. A calcium shortage causes the growth retardation on the body growth. In this study, we examined the therapeutic effects of calcium, vitamin D and egg yolk peptide (EYP) treatment on the retardation of the longitudinal bone growth induced by low-calcium diet in adolescent rats. Methods : Low calcium diets were administrated for 15 days. During the last five days, calcium and/or vitamin D and/or EYP were administrated. The body weights, longitudinal bone growth rates, the heights of growth plates, and bone morphogenetic protein (BMP)-2 and insulin-like growth factor (IGF)-1 expressions were measured using histochemical analysis. Results : Low calcium diets caused the significant reduction in body weight gains and the longitudinal bone growth. The heights of growth plates and the expressions of BMP-2 and IGF-1 showed the impairment of body growth as well. Calcium and/or vitamin D administration could not significantly increase the longitudinal bone growth. However, calcium, vitamin D, and EYP administration significantly increased the bone growth, the growth plate height, and BMP-2 and IGF-1 expressions. Conclusions : These results suggest that EYP enhances the longitudinal bone growth in the calcium and/or vitamin D deficiency and it could be a promising agent for the treatment of children suffering from malnutrition.

• Korean Journal of Clinical Pharmacy
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• v.29 no.4
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• pp.238-246
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• 2019

Background: In South Korea, as an aged society, an understanding of dementia and its risk factors is important from clinical and healthcare policy perspectives. Relationship between cognitive impairment and body weight or weight changes have been reported, but these were contradictory. We have evaluated the association between weight changes and cognitive decline using national level longitudinal data. Methods: Data from the Korean Longitudinal Study of Ageing from 2006 to 2012 were used. Association between weight changes and decline in cognitive function as measured by K-MMSE (the Korean version of the Mini-mental state examination) score was assessed by multivariate logistic regression. Weight changes were calculated from 1st wave and 3rd wave survey data, and classified into five groups as stable, increases, decreases of >10%, or 5%-10%. Results: About 37% of the total participants (n=4,512) were 65 years or older. These participants made up the largest proportion of the groups with weight change exceeding 10%. Multivariate logistic regression analyses revealed that weight changes exceeding 10% (10% increase vs stable, adjusted OR [aOR] 1.47, 95% confidence interval (CI) 1.11-1.95; 10% decrease vs stable, aOR 1.44, 95% CI 1.11-1.88) were significant predictive factors for decline in cognitive function. In subgroup analyses, the association between weight changes and cognitive decline was significant in males aged over 65 years and in normal BMI groups. Conclusion: Weight changes, both increases and decreases exceeding 10% of baseline, were significantly associated with declines in cognitive function among older adults in South Korea.

• Korean Journal of Health Education and Promotion
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• v.6 no.1
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• pp.75-90
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• 1989

This study tries to show the physical growth patterns and various adolescent characteristics by using longitudinal data for the height, weight, chest girth and sitting height of 1, 132 high school students in Seoul. And this study also tries to show what influencing factors on the physical growth of this aged population. The followings are the results. 1. The boys have their peak velocity of height when they are 12~13 years old. And the girls have when they are 10~11 years old. Peak velocity of weight for boys is at the age of 13~14. And for girls is at the age ofr11~12. Peak velocity of chest girth for boys is at the age of 12~13. And for girls is at the age of 11~12. Peak velocity of sitting height for boys is at the age of 13~14. And for girls is at the age of 11~13. So girls of this period grow more rapidly by around two years than boys. 2. The menarche of girls begins at the age of 12.4. So it begins 1.4 year before peak height velocity period. 3. Of life behavior boys contingency coefficient between essential time and height and weight is .5150 and .479 5, that between studying time and height and weight is .3344 and and .2912(In case of girls is .4735, .4321, .3247, .3134).

• Journal of Nutrition and Health
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• v.32 no.1
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• pp.75-82
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• 1999

In order to investigate the longitudinal changes on zinc secretion of lactating women and zinc intake of breast-fed infants, we examined 20 lactating women(10 primipare and 10 multipare) and their infants during the first 90 days postpartum. We measured the consumed volume of human milk by test-weighing method and zinc concentration by atomic absorption spectophotometry after wet digestion. Weight gain of infants was -5.7, 54.1, 46.3, 42.0 and 32.3g/day at 7, 15, 30, 60 and 90 days postpartum, respectively. The secretion volume of human milk was 527, 608, 724, 841 and 798g/day respectively. The consumed volume of human milk of breast-fed infants was 432, 503, 603, 715 and 715g/day. The intake level of breast milk to secretion volume reached 85.0% in average. The zinc concentration of the milk was 4.29, 3.32, 2.52, 1.62 and 1.18mg/l, and the zinc intake of breast-fed infants was 1.80, 1.69, 1.45, 1.15 and 0.70mg/day. Zine intake per body weight of infants averaged 0.32mg/kg/day during the first 90 days postpartum. The average zinc intake of breast-fed infants was 1.36mg/day, which is 27.2% of the recommended daily allowance for 0-4-month-old infants.

• Journal of the Ergonomics Society of Korea
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• v.6 no.2
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• pp.3-8
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• 1987

In order to secure reliable values of measurement of the data about children's longitudinal develop- ment and physique examination and their growth states for 6 years from first grade through sixth grade in elementary school was collected based on their school health records. A sample physique group and general physique group were investigated and compared classified into girls and boys. The results are as follows; (1) Whe the difference of physiques in the sample group and general group is compared, boys and girls show little difference in height but boys differ greatly in weight and sitting-height but girls do in weight, girth of chest and sitting-height between 8 and 11 years old. (2) In the verification of the two groups; the body height in 7 years old show a significant difference at the P<0.5 level and their weights do at 7.8 and 11 years old. Girls' sitting-height at 11 years old shows a significant difference at the P<0.5 level. In the light of the above results because possibility of instrumental error in measurement is high between the two groups and also in case of the comparison of past sample data, the physique examination used in every school seems to be in need of reconsideration to reduce errors in measurement.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2003.10a
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• pp.333-339
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• 2003

Recently, the bridges become greater according to development of a construction technology. This phenomenon requires long span bridge, so that increases the dead weight. The orthotropic steel deck bridges have much advantages such as the light dead weight and the reduction of construction period. And almost whole process of carried out is manufactured at factory, so it can cause the increase of quality authoritativeness. But orthotropic steel deck bridge is consist of structure by welding, it can not avoid a lot of welding jobs, defects and transformation by welding are becoming problem accordingly. Specially, topical stress concentration phenomenon in cross connection area of longitudinal and transverse rib causes fatigue failure. The Bulkhead Plate for prevention of this stress concentration phenomenon was applied by changing the orthotropic steel deck of Williamsburg bridge in USA. But, it is principle that a Bulkhead Plate is not established in the domestic design standard. Therefore, it is estimated that the study for installation of Bulkhead Plate is needed. This treatise with considering these circumstances proves efficiency of Bulkhead Plate and will be presented optimal design details through finite element analysis according to change the geometrical of Bulkhead Plate and tile cross-connection area of longitudinal and transverse rib.

• Journal of Nutrition and Health
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• v.26 no.4
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• pp.405-413
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• 1993

The longitudinal changes on human milk volume of 27 Korean lactating women (primiparae=10, multiparac=17) from 0.5 to 6 months after parturition have been studied by test-weighing method in Cheongju and Anseong area. The human milk volume per day increased to 2 months postpartum, and then decreased during lactation. The mean volume(g/day) at 0.5, 1, 2, 3, 4, 5, and 6 months were 634, 810, 847, 840, 844, 810, and 732g, respectively. The average volume were 791 ($\pm$149) and 786($\pm$131)g for primiparae and multiparae, respectively. The overall mean volume was 788$\pm$135g/day. The distributions of the individual mean volume during the first 6 months of lactation were found 450~549g(3.7%), 550~649g(11.1%), 650~749g(22.2%), 750~849%(37.1%), 850~949g(18.6%), 950~1049g(3.7%), and 1050~1149g(3.7%). The mean volume between primiparae and multiparase was significantly lower than other periods. The peak milk volume during the lactation was observed at 3 months postpartum for primiparae(40%), 2 months postpartum for multiparae(35.3%), and 2 months postpartum for total lactating women(29.6%). The volume of human milk had a significant positive correlation with peak volume and infant milk intake, but no correlation with maternal age, weight before delivery, height, and birth weight.

• The Journal of Korean Medicine
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• v.33 no.2
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• pp.1-10
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• 2012

Objectives: This study was aimed to investigate the effect of Bojungikgitang-gagambang (BJIG) on longitudinal bone growth in rats. Methods: The BJIG treated group (300 mg/kg) and the control group (vehicle) were administered orally twice daily for 4 days. To investigate the effects of BJIG we measured body weight gain. The bone growth effect was analyzed by measuring between fluorescent lines marked with tetracycline, which plays the role of fluorescent dye on the surface of the tibia. Tetracycline was intraperitoneally injected. The height of growth plates in the epiphyseal plate was measured. The expression of bone morphogenetic protein-2 (BMP-2) and insuline-like growth factor-1 (IGF-1) was investigated by immunohistochemistry. Results: BJIG caused a significant acceleration of longitudinal bone growth of $349.7{\pm}15.9{\mu}m/day$ compared to control ($319.8{\pm}21.4{\mu}m/day$). The height of overall growth plate was not significantly more compared to the control, but the size of cells in the proliferative zone and hypertrophic zone were. In the immunohistochemistry, BMP-2 and IGF-1 were expressed markedly in the proliferative or hypertrophic zone, respectively. Conclusions: BJIG stimulated the chondrocyte hypertrophy and chondrogenesis in the growth plate and directly increased the longitudinal tibia length of rats.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.1
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• pp.17-27
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• 2011

A selection experiment for reduced residual feed intake (RFI) in Yorkshire pigs consisted of a line selected for lower RFI (LRFI) and a random control line (CTRL). Longitudinal measurements of daily feed intake (DFI) and body weight (BW) from generation 5 of this experiment were used. The objectives of this study were to evaluate the use of random regression (RR) and nonlinear mixed models to predict DFI and BW for individual pigs, accounting for the substantial missing information that characterizes these data, and to evaluate the effect of selection for RFI on BW and DFI curves. Forty RR models with different-order polynomials of age as fixed and random effects, and with homogeneous or heterogeneous residual variance by month of age, were fitted for both DFI and BW. Based on predicted residual sum of squares (PRESS) and residual diagnostics, the quadratic polynomial RR model was identified to be best, but with heterogeneous residual variance for DFI and homogeneous residual variance for BW. Compared to the simple quadratic and linear regression models for individual pigs, these RR models decreased PRESS by 1% and 2% for DFI and by 42% and 36% for BW on boars and gilts, respectively. Given the same number of random effects as the polynomial RR models, i.e., two for BW and one for DFI, the non-linear Gompertz model predicted better than the polynomial RR models but not as good as higher order polynomial RR models. After five generations of selection for reduced RFI, the LRFI line had a lower population curve for DFI and BW than the CTRL line, especially towards the end of the growth period.