• Atmosphere
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• v.22 no.1
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• pp.87-96
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• 2012

Aerosol number concentration ($N_{CN}$), size distribution and cloud condensation nuclei (CCN) concentration ($N_{CCN}$) were measured during 16-21 August 2008 at Daegwallyeong (DG) located in the eastern rural region of the Korean Peninsula. In the very next week (22-29 August 2008) the same aerosol properties were measured at Yeongjong Island (YJ) in the Yellow Sea. $N_{CN}$ for all 3 size cuts (above 3, 6 and 10 nm) was significantly higher at DG than YJ, but $N_{CCN}$ was significantly lower at the former and resulted in the $N_{CCN}/N_{CN}$ ratio more than twice higher at YJ ($0.94{\pm}0.09$ vs. $0.35{\pm}0.15$ at 0.53% supersaturation). The geometric mean diameter at DG, $53{\pm}15nm$, was much smaller than that at YJ, $91{\pm}6nm$, due to the particle formation events that were likely to have occurred continuously at DG. For given mean diameter, aerosols were more likely to act as CCN at YG compared to those at DG.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.1
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• pp.65-70
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• 1997

In order to investigate the effect of ANP on surfactant secretion from alveolar type II cell(AT II cell) during circulatory derangement in adult respiratory distress syndrome (ARDS), the secretion of surfactant from AT II cells was evaluated in purely isolated AT II cultures from rat lungs. For the simulation of sympathetic stimulation during circulatory derangement, primary AT II cultures were incubatedwith isoproterenol and IBMX. In this isoproterenol stimulated AT II cells, ANP were added in the media for the investigation of effect of ANP on surfactant secretion from AT II cells. For the evaluation of surfactant secretion, $[^3H]-methylcholine$ was incorporated and the level of radiolabelled choline chloride secreted from the cells was determined. As previously reported, isoproterenol and IBMX stimulated surfactant secretion from AT II cells. Isoproterenol showed synergistic increase of surfactant secretion with IBMX in AT II cells. In isoproterenol stimulated AT II cells, physiological level of ANP inhibited the secretion of surfactant in primary cultures of AT II cells. On the basis of these experimental it is suggested that, in association with ciculatory change during ARDS, increased secretion of ANP by the pulmonary edema, hypoxia and congestive heart heart failure might aggravate the symptoms of ARDS by reduction of surfactant secretion from AT II cells.

• Journal of Nutrition and Health
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• v.28 no.5
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• pp.406-414
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• 1995

Nitrogen(N) concentration of preterm(PT) and term (T) milk in various fractions, such as total, protein, nonprotein, whey protein and casein were determined at 2-5 days, 1, 2, 4 and 6 weeks of postpartum. The purpose of this study was to investigate the nitrogen concentration of human milk from mothers delivering at preterm and term, and the propriety of preterm milk for premature infants. The concentration of total N, nonprotein N, protein N, whey protein N and casein N in preterm milk was decreased significantly with time postpartum. Total N was 374mg/이 at colostrum, 232mg/dl at mature milk. Whey protein N was decreased from 42mg/dl at 2-5 days to 32mg/dl at 4-6 weeks. Protein N was 332mg/dl at colostrum, 202mg/dl at mature milk. The proportion of whey protein N and casein N were 39:61 at colostrum, 28:72 at mature milk. No difference were found between T and PT milk for total nitrogen excepted 2 weeks. In this report we show that nitrogen concentration except casetpt casein N is smaller in milk from mothers giving birth prematurely than in milk from mothers giving birth at term, over the first two weeks of lactationl But protein N was higher in preterm milk than term milk, whey protein nitrogen was lower. By comparing predicted nitrogen intakes to estimated requirements of preterm infants fed 150 to 200ml/kg/day of their own mother's milk, we predict that the quantities of protein provided would be adequate to meet the requirements of the prematured infants during the early weeks of life.

• 전자공학회논문지 IE
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• v.49 no.2
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• pp.46-51
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• 2012

Transmit signal of Enhancement Layer in AT-DMB system is received by Coherent Detection, but in Base Layer of AT-DMB, a differential modulation and demodulation is adopted, same as the T-DMB. Especially for the coherent dectection of enhancement layer in AT-DMB system, a channel estimation must be employed. In this paper, I will show that the BER performance of Base-Layer in AT-DMB system will be improved by using the channel estimation information. The suggested method is focusing the constallations after Equalizaing to the nearlest ${\pi}$/4-shift DQPSK constallation points. Simulation results show that for the non-coding environment, the BER performance of AWGN channel, about 2-dB gain can be achieved at $10^{-4}BER$.

• Korean Journal of Child Studies
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• v.25 no.5
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• pp.147-161
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• 2004

This study was designed to explore developmental evaluation in healthy full-term, at risk preterm and full-term infants. Specifically the purposes of the study were to investigate Psychomotor Developmental Index(PDI) and Mental Developmental Index(MDI) based on Bayley Scales of Infant Development(1993). The subjects were 72 infants, 24 each for healthy full-term infants, 24 each for at risk preterm infants and 24 each for at risk full-term infants such as having neonatal asphyxia, hypoxic ischemic brain damage, respiratory distress syndrome. The data were analyzed through Kruskal-Wallis test and correlations to examine healthy full-term, at risk pre-term and at risk full-term infants. Results showed that there were significant differences among healthy full-term, at risk pre-term and at risk full-term infants in PDI and MDI. On the correlation with PDI and MDI, infants showed significant correlations. Early interventions for developmental improvement are required for functional outcome in these infants.

• The Journal of Korean Physical Therapy
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• v.25 no.1
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• pp.1-9
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• 2013

Purpose: This study sought to identify the utilization and confidence in assistive technology (AT) for pediatric physical therapists (PPTs) and pediatric occupational therapists (POTs) for the purpose of improving the utilization of AT in clinics. Methods: The subjects of this study were 167 therapists (98 PPTs and 69 POTs) who work at general hospitals, welfare centers, facilities for the disabled, and special education schools in Seoul and Gyeonggi province. The frequency analysis and chi-squared test were used. Results: This study found that both PPTs and POTs recognize that AT benefits infants with disabilities; however, they show low confidence in using AT. Applications of AT are concentrated on wheelchairs for mobility and assistance with seating position, with orthotics/prosthetics for both purposes. POTs were found to use a wider variety of AT devices. While both PPTs and POTs frequently select/recommend devices, both groups are less involved with delivery methods, manufacture of devices, and education on AT use. Conclusion: These findings show the actual conditions of utilization and confidence in AT of PPTs and POTs deeply involved with AT, and emphasize that AT training is essential for pediatric treatment by comparing domestic and foreign studies.

• Applied Microscopy
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• v.47 no.4
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• pp.242-250
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• 2017

The purpose of this study was to characterize the prenatal and postnatal development of the mouse parotid salivary gland and tooth, and to investigate the relationship between the developmental timing of the two organs. Development of parotid salivary gland begins on embryonic day 15 (E15), which is the prebud stage; E17 is the initial bud stage; E21 to postnatal day 3 (PN3) is the pseudoglandular stage; PN5 to PN10 is the canalicular stage; and PN21 is the terminal bud stage. At E15, the developing maxillary molar tissue is at the bud stage; at E17, it is at the cap stage; at E21, it is at the early bell stage; PN3 to PN5 comprises the advanced bell stage; at PN10, it is at the crown stage; at PN21, it is at the functional stage. Therefore, unlike the other major salivary glands, the development of mouse parotid salivary gland is completed through a process of prenatal and postnatal morphogenesis and becomes functional at about the same time as the developing tooth. The developmental completion times of the parotid salivary gland and tooth are closely related to the weaning time of animal.

• Restorative Dentistry and Endodontics
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• v.2 no.1
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• pp.50-54
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• 1976

16 healthy teeth extracted have been selected and their color and structural change have been observed at the fixed temperatures of $200^{\circ}F$., $400^{\circ}F$., $600^{\circ}F$., and $800^{\circ}F$. respectively at the intervals of 10min. 30min and 60min. The results were as follows: 1) $200^{\circ}F$ Groop: At the 60 minutes interval, crown surface shows pattern simliars to mottled teeth and roots take on light yellowish colar and interglobular dentin tends to be rough. 2) $400^{\circ}C$ Groop: at the 30 minutes interval, cracks begin to show in the direction of long axis of the teeth and crown surface have been observed on the verge of fracture at the 60 minutes interval. 3) $600^{\circ}F$ Groop: Crowns take on grayish-white color thoroughout 10, 30 and 60 minutes intervals and roots reveal black color. Moreover the seperation of enamel from dentin has been confirmed at the 60 minutes interval and inner dentin has changed black. 4) $800^{\circ}F$ Groop: Crowns take on the same grayish-white color as at the $600^{\circ}F$ at the 10, 30 and 60 minutes intervals and roots reveal gray color at the 30 and 60 minutes intervals, while parts of the crown have fractured at the 10 minutes interval. Inner dentin has turned gray at the 60 minutes interval.

• Journal of The Korean Society of Grassland and Forage Science
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• v.9 no.3
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• pp.135-140
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• 1989

This experiment was to study the relationship between shoot and root system in perennial ryegrass at different stages of growth. The results are summarized as follows; 1. The dry weight of shoot was significantly correlated with the dry weight of root at both stages of growth. 2. The yield components of shoot and root systems were changed by the stages of growth. Thus, the dry weights of shoot and root were positive correlated with the number of tillers and roots at 60 days after sowing. But, the dry weights of shoot and root were positive correlated with the dry weight of root, the dry weight of tiller, length of plant and length of root at 90 days after sowing. 3. Maprirna variety was obtained a higher dry weights of shoot and root at 60 days after sowing, but, Alta variety was obtained at 90 days after sowing, respectively. 4. The dry weight of shoot was positive correlated with leaf area at both stages of growth. 5. The dry weight of shoot was significantly negative correlated with specific leaf weight at 60 days after sowing, but positive correlated with specific leaf weight at 90 days afikr sowing. 6. The dry weight of root was smcantly positive correlated with leaf area at 60 days after sowing, but not recognized at 90 days after sowing.

• Journal of Technologic Dentistry
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• v.28 no.2
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• pp.367-373
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• 2006

This study was performed to observe the flow change of the inlay waxes at various temperatures. The flow of inlay waxes was tested according to the treatment conditions, for 10 minutes at 40$^{\circ}C$, 41$^{\circ}C$, 42$^{\circ}C$, 43$^{\circ}C$, 44$^{\circ}C$, and 45$^{\circ}C$ The flow of inlay waxes at various temperatures was measured with an electro dial gauge. The results were as fellows: 1. The flow change of the inlay waxes at various temperatures was shown to increase in the order of wax A, B, D, C. 2. Wax A was close to ADA specification with 3% flow at 40$^{\circ}C$ and 71% flow at 45$^{\circ}C$, but wax B and D did not reach up to ADA specification with 40% flow at 45$^{\circ}C$. 3. Wax C came up with 3% flow at 40$^{\circ}C$ and 7% flow at 45$^{\circ}C$, and it revealed a very low flow change at 5$^{\circ}C$.