• Journal of Nutrition and Health
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• v.41 no.2
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• pp.156-164
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• 2008

The purpose of this study was to investigate factors related to bone mineral contents (BMC) at os calcis of adolescents. The subjects were 604 students (327 boys and 277 girls) between 7th and 9th grade in Seoul, Korea. The mean age was 14.2 ${\pm}$ 0.9 years. General characteristics were collected by a questionnaire, bone mineral contents (BMC) were measured in os calcis by Duel Energy X-ray Absorptiometry (PIXI, General Electronics, USA) and height and weight were measured by bioelectrical impedance analysis method (Inbody 4.0, Biospace Co. Ltd, Seoul, Korea). Mean BMC of os calsis were 2.241 g. Height (p <.0001), weight (p <.0001I), BMC (p <.0001I) ofboys were higher than those of girls. Percent body fat of girls, however, was higher than that of boys (p <.0001). Anthropometric measurement, pocket money, sibling, experience of fracture, pubertal stage, intake of supplements, physical or outdoors activity, and eating habit had significant influence on BMC of boys. Anthropometric measurement, physical or outdoors activity, and eating habit had significant influence on BMC of girls. Multivariate regression with adjustment for sex and age showed that BMC was associated positively with height, BMI, frequency of regular activity, and intake of spinach or radish leaves (all p <0.05), and negatively with percent body fat (p <.0000 and Korean traditional diet pattern (p = 0.01). On the basis of these results, it is recommended to develop nutrition education and physical activity program for adolescents to improve BMC and prevent osteoporosis.

• Geophysics and Geophysical Exploration
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• v.9 no.4
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• pp.279-290
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• 2006

The borehole radar methods used to tunnel detection are mainly classified into borehole radar reflection, directional antenna, crosshole scanning, and radar tomography methods. In this study, we have investigated the feasibility and limitation of each method to tunnel detection through case studies. In the borehole radar reflection data, there were much more clear diffraction signals of the upper wings than lower wings of the hyperbolas reflected from the tunnel, and their upper and lower wings were spreaded out to more than 10m higher and lower traces from the peaks of the hyperbolas. As the ratio of borehole diameter to antenna length increases, the ringing gets stronger on the data due to the increase in the impedance mismatching between antennas and water in the boreholes. It is also found that the reflection signals from the tunnel could be enhanced using the optimal offset distance between transmitter and receiver antennas. Nevertheless, the borehole radar reflection data could not provide directional information of the reflectors in the subsurface. Direction finding antenna system had a advantage to take a three dimensional location of a tunnel with only one borehole survey even though the cost is still very high and it required very high expertise. The data from crosshole scanning could be a good indicator for tunnel detection and it could give more reliable result when the borehole radar reflection survey is carried out together. The images of the subsurface also can be reconstructed using travel time tomography which could provide the physical property of the medium and would be effective for imaging the underground structure such as tunnels. Based on the results described above, we suggest a cost-effective field procedure for detection of a tunnel using borehole radar techniques; borehole radar reflection survey using dipole antenna can firstly be applied to pick up anomalous regions within the borehole, and crosshole scanning or reflection survey using directional antenna can then be applied only to the anomalous regions to detect the tunnel.

• Tuberculosis and Respiratory Diseases
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• v.51 no.6
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• pp.570-578
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• 2001

Background: With cases of chronic obstructive pulmonary disease(COPD), weight loss and low body weight have been found to correlate with increased mortality and poor prognosis. Therefore, nutritional aspects are an important part of the treatment in cases of COPD. In Korea, there is only limited data available for the changes of resting pulmonary function in relation to nutritional status. This study was carried out to investigate the differences of resting pulmonary function in relation to the nutritional status of patients with COPD. Method : 83 stable patients, with moderate to severe COPD, were clinically assessed for their nutritional status and resting pulmonary function. The patients' nutritional status was evaluated by body weight and fat-free mass (FFM), which was assessed by bioelectrical impedance analysis. According to their nutritional status, the 83 patients were divided into two groups, designated as the depleted, and non-depleted, groups. Result : Of the 83 patients, 31% were characterized by body weight loss and depletion of FFM, whereas 28% had either weight loss or depleted FFM. In the depleted group, significantly lower peak expiratory flow rate(p<0.05) and Kco(p<0.01), but significantly higher airway resistance(Raw, p<0.05) were noted. There was no difference for the non-depleted group in forced expiratory volume at one second, residual volume, inspiratory vital capacity, or total lung capacity. Maximal inspiratory pressure($P_{Imax}$) was also significantly lower in the depleted group(p<0.05). Conclusion : We conclude, from our clinical studies, that nutritional depletion is significantly associated with the change in resting pulmonary function for patients with moderate to severe COPD.