• Journal of Plant Biology
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• v.38 no.3
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• pp.305-317
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• 1995

The bryophyte communities on the forest floor of the mixed coniferous, deciduous broad-leaf forest and the evergreen coniferous forest of cool temperate and subalpine zones in Chiri Mountains with the highest peak (Cheonwangbong 1915 m) in south-central part of the Korean Peninsula were investigated from the phytosociology viewpoint. As a result, five bryophyte communities were recognized, considering the species composition of vascular vegetation; A. Sasamorpha borealis-Abies koreana/Dicranum scoparium-Plagiothecium silvaticum community, B. Bosta minor-Abies koreana/Anomodon rugelii-Plagiomnium cuspidatum community, C. Abies koreana/Hylocomiopsis ovicarpa-Entodon rubicundus community, D. Abies koreana-Picea jezoensis/Hylocomiopsis ovicarpa-Thuidium kanedae community, E. Abies koreana-Pieea jezoensis/Hylocomium splendens-Pleurozium sehreberi community. Among these, the communities A, B, C and D were distributed in the mixed coniferous and deciduous broad-leaf forest of lower altitudes (1200 to 1700 m) and characterized by the elements of the cool temperate zone. They were confimled as synusies belonging to the Fraxino-Abietetum koreanae Song 1988. The community E was distributed in higher altitudes (1700 m to near the summit) and characterized by the species group of the holarctic elements, e.g. Hyloeomium splendens, Pleurozium sehreberi, Dieranum majus, etc. limited in subarctic; subalpine and arctic; alpine zones. The community E was confirmed as a synusie of the Abieti koreanae-Piceetum jezoensis Song 1991 belonging the Vaecinio-Pieeetea Br.-BI. 1939. Up to date many investigator have described the coniferous forest distibuted above 1200 m in Chiri mountauns as the forest vegetation of subalpine zone. However, from the results of the present study, the boundary of the mixed forest and the true subalpine coniferous forest was elucidated to be ca. 1700 m phytosociologically. Species richness was highest in the community E, and the other four communities showed a similar species richness. Among the species diversity indices, H' and D were high in the communities Band E, low in the communities A and C, and medium in the community D. The values of J' decreased with the increase in altitudes and the community E showed the lowest value. The result of Bray-Curtis ordination revealed that the diversity analysis and the division of the above two forest zones are justifiable. The taxa of the bryophyte communities were composed of 25 families, 46 genera, 73 species, 1 subspecies and 2 varieties.

• Journal of Chest Surgery
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• v.32 no.4
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• pp.347-352
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• 1999

Background: The atrial fibrillation in patients with mitral valvular heart disease is frequently converted to sinus rhythm after the mitral valve surgery. This sinus restoration implies an important meaning in that it not only helps postoperative convalescence in patients with unstable hemodynamics but also reduces the rate of postoperative thromboembolism. Material and Method: We retrospectively analyzed 184 patients who received mitral valve surgery from June 1986 to December 1996 to investigate the trend of rhythm change following mitral valve surgery and thus to clarify the predisposing factors of postoperative sinus rhythm conversion and its maintenance. Result: The sinus rhythm was restored after the operation in 54 out of 139 patients with atrial fibrillation preoperatively(38.8%). However, the atrial fibrillation recurred in 41 patients at the time of discharge showing a recurrence rate of 75.9 percent. The mean duration of sinus rhythm in patients with eventual atrial fibrillation recurrence was 8.2${\pm}$5.9 days. Only 15 patients were in sinus rhythm at the time of late follow-up with the mean follow-up period of 84.4${\pm}$34.7 months. While the age, duration of symptoms, duration of atrial fibrillation, left atral size, and pulmonary artery pressure were thought to be the predisposing factors for sinus conversion after the operation, only the duration of atrial fibrillation and ejection fraction were considered risk factors for the recurrence of the atrial fibrillation following sinus conversion. Conclusion: This study suggests that the early operation is mandatory for the satisfactory result regarding postoperative rhythm. Moreover, additional operative measure in adjunct to the intervention of mitral valve should be considered for the maintenance of restored sinus rhythm as reflected by high postoperative recurrence rate of atrial fibrillation.

• Journal of the Korean earth science society
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• v.28 no.6
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• pp.720-732
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• 2007

For the Seoul metropolitan area and the eastern Kyeongsang Basin, we simultaneously calculated $Q_P^{-1}$ and $Q_S^{-1}$ by applying the extended coda-normalization method for 98 seismograms of local Earthquakes. As frequency increases from 1.5 Hz to 24 Hz, the result decreased from $(4.0{\pm}9.2){\times}10^{-3}$ to $(4.1{\pm}4.2){\times}10^{-4}$ for $Q_P^{-1}$ and $(5.5{\pm}5.6){\times}10^{-3}$ to $(3.4{\pm}1.3){\times}10^{-4}$ for $Q_S^{-1}$ in Seoul Metropolitan Area. The result of eastern Kyeongsang basin also decreased from $(5.4{\pm}8.8){\times}10^{-3}$ to $(3.7{\pm}3.4){\times}10^{-4}$ for $Q_P^{-1}$ and $(5.7{\pm}4.2){\times}10^{-3}$ to $(3.5{\pm}1.6){\times}10^{-4}$ for $Q_S^{-1}$. If we fit a frequency-dependent power law to the data, the best fits of $Q_P^{-1}$ and $Q_S^{-1}$ are $0.005f^{-0.89}$ and $0.004f^{-0.88}$ in Seoul metropolitan Area, respectively. The value of $Q_P^{-1}$ and $Q_S^{-1}$ in the eastern Kyeongsang basin are $0.007f^{-1.02}$ and $0.006f^{-0.99}$, respectively. The $Q_S^{-1}$ value of the eastern Kyeongsang basin is almost similar to Seoul metropolitan area. But the $Q_P^{-1}$ value of the eastern Kyeongsang basin is a little higher than that of Seoul metropolitan area. This may be that the crustal characteristics of the eastern Kyeongsang basin is seismologically more heterogeneous. However, these $Q_P^{-1}$ values in Korea belong to the range of seismically stable regions all over the world.

• Progress in Medical Physics
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• v.24 no.1
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• pp.25-34
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• 2013

To investigate effects of phase mask on susceptibility-weighted images (SWI) using voxel-based analyses in normal elderly subjects. A three-dimensional (3D) gradient echo sequence ran to obtain SWIs in 20 healthy elderly subjects. SWIs with two (SWI2) and four (SWI4) phase multiplications were achieved with positive (PSWI) and negative (NSWI) phase masks to investigate phase mask effects. The voxel-based comparisons were performed using paired t-tests between PSWI and NSWI and between SWI2 and SWI4. Differences of signal intensities between magnitude images and SWI4 were larger than those between magnitude images and SWI2s. Differences of signal intensities between magnitude images and PSWIs were larger than those between magnitude images and NSWIs. Moreover, the signal intensities from NSWI2s and NSWI4s were greater than those from PSWI2s and PSWI4s, respectively. More differences of signal intensities between NSWI4 and PSWI4s were found than those between NSWI2s and PSWI2s in the whole brain images. The voxel-based analyses of SWI could be beneficial to investigate susceptibility differences on the entire brain areas. The phase masking method could be chosen to enhance brain tissue contrast rather than to enhance venous blood vessels. Therefore, it is recommended to apply voxel-based analyses of SWI to investigate clinical applications.

• Radiation Oncology Journal
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• v.25 no.2
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• pp.101-108
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• 2007

[ $\underline{Purpose}$ ]: To compare radiation therapy alone to combined modality therapy about survival rate and tolerance of elderly patients ($70=or{\geq}$) with non-small-cell lung cancer (NSCLC). $\underline{Materials\;and\;Methods}$: Between 1998 and 2002, 57 patients given radiation therapy due to NSCLC (Stage III) were analysed retrospectively. Radiation therapy alone (RT), concurrent chemoradiation (CRT), and sequential chemoradiation (SCRT) was done to 33, 16 and 8 patients, respectively. Patients' median age was 74 (range $70{\sim}85$). Male and female are 51 patients and 6 patients, respectively. 23 patients were stage IIIa and 34 were stage IIIb. Patients' characteristic distribution of RT and CRT was not significantly different except mass size that RT has a bigger than CRT. The fraction size of radiation therapy was 1.8 Gy in CRT and $1.8{\sim}3\;Gy$ in other groups. Total radiation dose was $51{\sim}63\;Gy$ according to the fraction size. If the prescribed total radiation dose was successfully irradiated, we stated that it was completion of radiation therapy. $\underline{Results}$: 52 patients were dead. Median period of radiation therapy was as follow: RT, 35 days, CRT, 60.5 days and SCRT, 35 days. Overall median survival time (MST) was 10.1 months. The 1 yr- and 2 yr-overall survival rate was 39.8% and 17.6%, respectively. MST of RT, CRT and SCRT was 8.9, 8.2 and 11.7 months, respectively. The 1 yr survival rate of RT, CRT and SCRT was 38.4%, 37.5% and 50% (not significant). Patients given incomplete radiation therapy were 12 (RT, 5 CRT, 6 SCRT, 1). N stage (p=0.081) and the difference of treatment methods (p=0.079) were the factors affecting incompletion of radiation therapy, but it was not significant. In case of combined-agents chemotherapy, 4 of 8 ceased radiation therapy. T stage ($T{\geq}3$), mass size (${\geq}5\;cm$), Karnofsky performance scale (${\leq}70$) and completion of radiation therapy were the prognostic factors in uni- and multi-variate analysis. $\underline{Conclusion}$: In elderly patients with NSCLC, radiation therapy alone was a treatment method with similar survival period compared with other methods. Generally, patients given radiation therapy alone was tolerable to a treatment. Before planning concurrent chemoirradiation in elderly patients with NSCLC, physicians pay attention to a selection of patients and chemotherapy agents considering general condition and toxicity.

• Journal of Food Hygiene and Safety
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• v.6 no.1
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• pp.1-12
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• 1991

Fischer 344 rats aged six weeks were diYided into four groups and group 1, 2, and 3 of rats were given an intraperitoneal injection of diethylnitrosamine at 200 mg/kg body weight and group 4 was given saline alone. Two weeks after beginning of the experiment, group 1 and 2 of rats were begun to feed on diets containing 0.02% 2-acetylaminofluorene as a promoter for four weeks. Three weeks after beginning of the experiment, all groups were performed partial hepatectomy. During the last two weeks, group 1 and 3 of rats were received subcutaneously 3 consecutive weekly doses of iron dextran at 0.125 ml/100 g body weight. Subcutaneous injection of iron dextran resulted in hepatic siderosis in group 1 and 3 of rats. Pre neoplastic nodules were identified histopathologically by two markers, resistance to exogenous iron accumulation and glutathione S-transeferase placental form (GST-P) activity, while early carcinogen induced foci were hardly resistant to iron accumulation and though a few lesions were identified, it could hardly be distincted from normal hepatocytes of surroundings. However, GST-P positive nodules as well as foci were clearly distincted from normal hepatic cells of surroundings. In the quantitative analysis of carcinogen-induced nodules and foci, more lesions were detected by immunohistochemical method for GST-P than by prussian blue staining for resistant to iron accumulation. It is concluded that immunohistochemical marker for GST-P is more sensitive and reliable than iron-resistance marker, and that iron-resistance is not useful marker for early detection of carcinogen-induced hepatic lesions.

• Korean Journal of Agricultural and Forest Meteorology
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• v.1 no.2
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• pp.127-134
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• 1999

This study was performed to obtain the basic data to present rational silvicultural tending plan. It makes these widely distributed pine-oak mixed stand and each of pure stand in middle province on object of this study and do comparative analysis of light condition about stand parameter and natural regeneration according to each slope(north, west and south) conditions of location in central part of South Korea. Sample plots for pine-oak mixed stand and pine and oak pure stand were established on each of southern, northern and western slopes based upon site and growth conditions of the slope. Sample plot was a circle of 0.05ha with a diameter of 25.24 m. A sample plot has between 30 and 40 tree in it. Total 23 sample plots were established; 9 pure pine stands, 8 pine-oak mixed stands. and 6 pure oak stands across lower, middle, upper parts of slopes. Relative light intensity within a stand was' measured by crown- photo(fish-eye lens; 180$^{\circ}$) system through fish-eye lens and by comparing each plot with the denuded through PAR-sensor. The crown closure ratio of pure pine stand (75%) shows much lower than that of mixed stand (90.9%) and pure oak stand (93%). The relative light intensity within a stand showed an opposite result. The crown closure of mixed stands tended to become gradually low as the slope moves from the north to the south, but the relative light Intensity within the stand tended to rise. By analyzing the relationship between the relative light intensity within a stand and stand parameter, light intensity within a stand tended to decrease as the diameter and N/ha increase. Number of oak seedlings and light intensity within a stand is in a straight-line regression relation. In particular, the number of oak seedlings was the highest in mixed stands on the southern slope. But no single pine seedling was found. The unfavorable conditions of l0cm thick litter layer and low relative light intensity in a stand (ranging between 4% and 8%) is considered to prevent pine seeds from germinating.

• Journal of the Korean Geotechnical Society
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• v.32 no.10
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• pp.41-53
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• 2016

Stability of the braced earth wall in the composite ground, which is composed of the jointed base rocks and the soil strata depends on the earth pressure acting on it. In most cases, the earth pressure is calculated by the empirical method, in which base rocks are considered as a soil strata with the shear strength parameters of base rocks. In this case the effect of the joint dips of the jointed base rocks is ignored. Therefore, the calculated earth pressure is smaller than the actual earth pressure. In this study, the magnitude and the distribution of the earth pressure acting on the braced wall in the composite ground depending on the joint dips of the base rocks and the ratio of soil strata and base rocks were experimentally studied. Two dimensional large-scale model tests were conducted in a large scale test facility (height 3.0 m, length 3.0 m and width 0.5 m) by installing 10 supports in a scale of 1/14.5. The test ground was presumed with the base rock ratio of the composite ground of 65%:35% and 50%:50% and with the joint dips for each base rock layer, $0^{\circ}$, $30^{\circ}$, $45^{\circ}$ and $60^{\circ}$, respectively. And then finite element analyses were performed in the same condition. As results, the earth pressure on the braced wall increased as the base rock layer's joint dips became larger. And earth pressure at the rock layer increased as the rock rate became larger. The largest earth pressure was measured when the base rock rate was 50% (R50) and the rock layer's joint dips was $60^{\circ}$. Based on these results, a formular for the calculation of the earth pressure in the composite ground could be suggested. Distribution of earth pressure was idealized in a quadrangular form, in which the magnitude and the position of peak earth pressure depended on the rock ratio and the joint dips.

• Food Science and Preservation
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• v.24 no.7
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• pp.923-933
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• 2017

This study was carried out to examine the quality characteristics of Doenjang manufactured with or without soaking Meju in brine according to salt concentrations (8 and 12%) during fermentation for 6 months. The moisture content and salinity of Doenjang fermented for 6 months were 54.9-60.3% and 7.8-12.5%, respectively. Doenjang using soaking Meju in brine had higher pH and lower titratable acidity than that using non-soaking Meju. The reducing sugar content in all samples was increased until 2 months and then decreased regardless of soaking Meju, especially that of non-soaking 8% Doenjang was the highest. The 8% low-salt Doenjang was shown the highest amino-type nitrogen content, especially the soaking Doenjang was higher than the non-soaking Doenjang. ${\alpha}$-amylase activity of all samples during fermentation were continuously decreased from 0.91-0.94 Unit/g to 0.01-0.06 Unit/g, especially the 8% soaking Doenjang was shown the highest activity after 2 months. Total bacterial count of the soaking Doenjang at the 6 months was in range of 7.8-8.0 log CFU/g and that of the non-soaking Doenjang was in range of 7.2-7.5 log CFU/g. By taste analysis, the 8% soaking Doenjang was shown the similar taste pattern with commercial Doenjang. In conclusion, the 8% low-salt Doenjang manufactured with soaking Meju in brine was a suitable concentration in order to reduce salt intake.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.669-675
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• 2001

The objective of this study was to examine the effects of antioxidant vitamins on the formation of $AFB_{1}-DNA$ adduct and $AFB_{1}-inducing$ cellular oxidative damage. Intraperitoneal(i.p.)injections of 10 mg/kg vitamin C(VC) and 63.8 mg/kg vitamin E(VE) were repeatedly administrated 4 times with 2 days interval to 6 week old male ICR mice. After one hour of vitamin treatments, 0.4 mg/kg $AFB_1$ was injected in $AFB_1$ plus vitamin treated groups by same way. On the other hands, $AFB_1$ treated group was only injected with $AFB_1$ by the same method described above without vitamins. According to quantitative analysis of the $AFB_1$ in mice serum by indirect competitive ELISA, 12.28 and 18.78 ng/mL were detected in $AFB_1-treated$ groups, but 7.60 and 4.85 ng/mL in $AFB_1$ plus VC and VE treated groups, respectively. 23.78, 25.48 ng/mL of $AFB_1-DNA$ adduct were detected in mice liver of $AFB_1$treated groups, while 5.26, 7.81 ng/mL in $AFB_1$ plus VC and VE treated groups, respectively. Consequently, the differences in the concentrations of $AFB_1$ related materials between vitamin treated and non-treated groups were significant. Immunohistochemistry revealed brownish infiltration of $AFB_1$ around central vein and sinusoid in $AFB_1-treated$ group. This manifestation was distinctly reduced in $AFB_1$ plus VC and VE treated groups.