• Journal of Radiation Protection and Research
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• v.6 no.1
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• pp.25-30
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• 1981

A measurement has been made for the radioactivities (or concentrations) of radon daughters, i.e., RaA, RaB and RaC in airborne dust by means of single filtering method. This is to evaluate the radioactivities in terms of Ci or WL (working level) from gross alpha counts measured in the selected-time intervals after an air sample is taken from a membrane filter paper with a mean pore size of $0.8{\mu}m$. This work involves determinations of standard deviation in radioactivities, radioactive equilibrium factor and ratio. It appears that a concentration of total radon daughters is $0.30{\sim}2.36pCi/l\;or\;0.89{\times}10^{-3}{\sim}6.57{\times}10^{-3}WL$, depending on the sampling time. Generally the highest concentration was observed around nine o'clock in a day while the lowest value was obtained around seventeen o'clock. Standard deviations based on counting statistics of RaA's, RaB's and RaC's concentrations are ${\pm}57.75%,\;{\pm}22.32%\;and\;{\pm}31.29%$, respectively. It is revealed that the radioactive equilibrium factor is 0.322 while the radioactive equilibrium ratio is of pattern $C_1>C_2>C_3$ in general. Here $C_1,\;C_2\;and\;C_3$ stand for concentrations of RaA,RaB and RaC, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.4
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• pp.498-506
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• 2014

The objective of this study was to investigate the beneficial effects of mulberry extract (MBE) on blood flow improvement. The $SC_{50}$ value for the DPPH radical scavenging activity of MBE was $89.36{\pm}5.46{\mu}g/mL$. Analysis of the cellular toxicity of MBE on RAW 264.7 and HepG2 cells showed no toxicity under a concentration of 2,500 ${\mu}g/mL$. We found that MBE inhibited the enzyme activity of cyclooxygenase (COX)-2 as well as oxidation of human LDL. Western blotting analysis showed that MBE inhibited protein expression of COX-2 and 5-lipoxygenase in RAW 264.7 cells. In addition, MBE inhibited protein expression of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 in human umbilical vein endothelial cells. Furthermore, MBE reduced the serum levels of total cholesterol and C-reactive protein in a concentration-dependent manner. These results both in vitro and in vivo suggest that MBE can be employed for the improvement of blood flow.

• Journal of Korea Foresty Energy
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• v.19 no.2
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• pp.93-101
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• 2000

Wood of Robinia pseudoacacia and bark of Populus alba$\times$P. glandulosa, Fraxinus rhynchophylla and Ulmus davidiana var. japonica were collected and extracted with acetone-water(7:3, v/v) in glass jar to examine whether its bioactive compounds exist. The concentrated extracts were fractionated with hexane, chloroform, ethylacetate and water, and then freeze-dried for column chromatography and bioactive tests. The isolated compounds were sakuranetin-5-O-$\beta$-D-glucopyranoside from Populus alba $\times$Pl glandulosa, 4--ethyoxy-(+)-leucorobinetinidin frm R. pseudoacacia and fraxetion from F. rhynchophylla and were characterized by $^1H$ and$^{13}C $ NMR and positive FAB-MS. Decay-resistant activity was expressed by weight loss ratio and hyphae growth inhibition in the wood dust agar medium inoculated wood rot fungi. R. pseudoacacia showed best anti-decaying property in both test and its methanol untreated samples, indicating higher activity than methanol treated samples in hyphae grwoth test. In antioxidative test, $\alpha$-tocopherol, one of natural antioxidants, and BHT, one of synthetic antioxidants, were used as references to cmpare with the antioxidant activities of the extacted fractions. Ethylacetate fraction of F. rhynchophylla bark indicated the hightest activity in this test and all fractions of R. pseudiacacia extractives also indicated higher activities compared with the other fractions. In the isolated compounds, aesculetin isolated from F. rhynchophylla bark showed best activity and followed by robonetinidin from R. pseudoacaica.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.5
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• pp.255-264
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• 2017

To evaluate the water quality changes in agricultural reservoir covered with floating photovoltaic solar-tracking systems, the water quality variations with time and depth were monitored on both six sites for light blocking zones and four sites for light penetration zones after the installation of floating photovoltaic solar-tracking systems in Geumgwang reservoir at Anseong-si, Kyeonggi province. For one year with 16 monitoring events, water quality parameters [i.e., water temperature, pH, dissolved oxygen (DO), chlorophyll-a (Chl-a), and blue-green algae (BGA)] were monitored at depths of 0.3 m, 1 m, 3 m, and 5 m, while chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) were monitored at depths of 0.3 m. Statistically, the difference in all water quality parameters was not significantly different (p > 0.05) at the level of significance of 0.05. Based on these results, the water quality data from light blocking zones (site 1~6) and light penetration zones (site 7~10) were clustered, and were compared with time and depth. As a result, the difference in water temperature, pH, DO, COD, TN, TP, Chl-a, and BGA between light blocking zones and light penetration zones was not significant (p > 0.05) with different time and depth. For Chl-a and BGA, some data from light blocking zones greater than light penetration zones were temporary observed due to the severe drought, low water storage rate, and over growth of periphyton. However, this temporal phenomenon did not impact the water quality. Considering the small water surface area (${\leq}0.5%$) covered by floating photovoltaic solar-tracking systems, the mixing effect of whole Geumgwang reservoir caused by Ekman current and continuous discharge were more dominant than the effect of reduced solar irradiance. Further study is warranted to monitor the changes in water quality and aquatic ecosystems with greater water surface area covered by floating photovoltaic solar-tracking systems for a long time.

• Journal of Distribution Science
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• v.10 no.1
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• pp.43-52
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• 2012

With the slowdown in environmental issues and the change of environmental consciousness, ecotourism is being discussed in various social fields. Ecotourism is being popularized for environmental protection, and now it is becoming a mainstream product from one of mass tourism. Ecotourism's emphasis on sustainable development in the tourism destination's society, economy, and environment, through ecotourism study and education, enable people to understand the core value of the ecological environment. 2011 was nominated as "the Year of World Forest" by the UN. In the recent years, forests are becoming increasingly important with their own values and functions in environment, economy, society, and culture. In particular, the global environmental issues caused by climate change are becoming an international agenda. Forests are the only effective solution for the carbon dioxide that causes global warming. Moreover, forests constitute a major part of ecotourism, and are now most used by ecotourists. For example, Korea, wherein 60% of the land is forest, attracts ecotourists. With the increasing interests in environment, the number of tourists visiting the ecosystem forest, which is highly valued for its conservation, is increasing significantly every year and is receiving considerable attention from the government. However, poor facilities in the forest ecotourism sites and improper market strategies are the reasons for the poor running of these sites. Furthermore, tourists' environmental awareness affects ecology environmental pollution or the optimization of forest ecotourism. In order to verify the relationships among tourist attractiveness, environmental consciousness, charm degrees of the attractions, and attitudes after tours, we established some scales based on existing research achievement. Then, using these scales, the researcher completed the questionnaire survey. From December 20, 2010 to February 20, 2011, after conducting surveys for 12 weeks, we finally obtained 582 valid questionnaires, from a total of 700 questionnaires, that could be used in statistical analysis. First, for the method of research and analysis, the researcher initially applied the Cronbach's (Alpha) for verifying the reliability, and subsequently applied the Exploratory factor analysis for verifying the validity. Second, in order to analyze the demographics, the researcher makes use of the Frequency analysis for the AMOS, measurement model, structural equation model computing, and also utilizes construct validity, convergent validity, discriminant validity, and nomological validity. Third, for the analysis of the ecotourists' environmental consciousness, impacts on tourist attractiveness, charm degrees of the attractions, and attitudes after the tour, the researcher uses AMOS 19, with the path analysis and equation of structure. After the research, researchers found that high awareness of natural protection lead to high tourist motivation and satisfaction and more positive attitude after the tour. Moreover, this research shows the psychological and behavioral reactions of the ecotourists to the ecotourist development. Accordingly, environmental consciousness does not affect the tourist attractiveness that has been interpreted as significant. Furthermore, people should focus on the change of natural protection consciousness and psychological reaction of ecotourists while ensuring the sustainable development of ecotourists and developing some ecotourist programs.

• The Korean Journal of Pharmacology
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• v.30 no.3
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• pp.273-289
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• 1994

Reversible brain ischemia was produced by occluding both common carotid arteries for 5 min, and the effects of aminoguanidine (AG), $DL-{\alpha}-difluoromethylornithine$ (DFMO), MK-801, and nimodipine (NM) on the ischemia induced changes of the polyamine, glutamate and acetylcholine levels in the hippocampus CA1 subfield and the specific $[^3H]\;MK-801$ binding to the hippocampus synaptosomal membranes were studied with a histological reference of the cresyl violet stained hippocampus. The basal putrescine level $(PT:\;74.4{\pm}8.8\;nM)$ showed a rapid increase (up to 1.7 fold) for 5 min of ischemia, remained significantly increased for 6 h, and then resumed the further increase to amount gradually up to about 3 fold 96 h after recirculation. However, the level of spermidine was little changed, and the spermine level showed a transient increase during ischemia followed by a sustained decrease to about 40% of the preischemic level after recirculation. The increase of PT level induced by brain ischemia was enhanced with AG or MK-801, but it was reduced by DFMO or NM. The basal glutamate level $(GT:\;0.90{\pm}0.l4\;{\mu}M)$ rapidly increased to a peak level of $8.19{\pm}1.14\;{\mu}M$ within 5 min after onset of the ischemia and then decreased to the preischemic level in about 25 min after recirculation. And NM reduced the ischemia induced increase of GT level by about 25%, but AG, DFMO and MK-801 did not affect the GT increase. The basal acetylcholine level $(ACh:\;118.0{\pm}10.5\;{\mu}M)$ did little change during/after brain ischemia and was little affected by AG or NM. But DFMO and MK-801, respectively, produced the moderate decrease of ACh level. The specific $[^3H]\;MK-801$ binding to the hippocampus synaptosomal membrane was little affected by brain ischemia for 5 min. The control value (78.9 fmole/mg protein) was moderately decreased by AG and MK-801, respectively but was little changed by DFMO or NM. The microscopic findings of the brains extirpated on day 7 after ischemia showed severe neuronal damage of the hippocampus, particularly CA1 subfield. NM and AG moderately attenuated the delayed neuronal damage, and DFMO, on the contrary, aggravated the ischemia induced damage. However, MK-801 did not protect the hippocampus from ischemic damage. These results suggest that unlike to the mode of anti-ischemic action of NM, AG might protect the hippocampus from ischemic injury as being negatively regulatory on the N-methyl-D-aspartate (NMDA) receptor function in the hippocampus.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.3
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• pp.209-214
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• 2010

Purpose: The purpose of this study was to investigate whether the re-osseointegration of the implants that had mechanical unscrewing possibly occurred or not. Furthermore, if it happened, the degree of re-osseointegration was evaluated by comparing with previous osseointegration. Materials and methods: The smooth implant (commercial pure titanium 99%) specimens, whose diameter and length was 3.75 mm, 4 mm, respectively were produced. Two implants were inserted into each tibia of 7 New Zealand female white rabbits weighing at least 3.0 kg. The torque removal force for each implant after 6 weeks of implants placement was measured and included in group I. The torque removal forces were assessed after the fixtures were re-screwed to original position and the subjects were allowed to have 4 more weeks for healing and included in group II. One rabbit was sacrificed after first measurement and produced 4 slide specimens in group I, and two rabbits were sacrificed after 2nd measurement, 7 slide specimens, in group II for histomorphologic investigations. All slide specimens were assessed based on the proportion of BIC (bone-implant contact) as well as CBa (Bone area in the cortical passage) value produced by counting the screw threads embedded in the compact bones under the optical microscopic analysis (${\times}20$). Statistical analysis was conducted to evaluate the torque removal force, BIC and CBa between group I and II. Results: As for the torque removal force, the result was $10.8{\pm}3.6$ Ncm for group I and $20.2{\pm}9.7$ Ncm for group II. Furthermore, the torque removal force of group II increased by 98.1% in average compared to group I (P<.05). On the other hand, histomorphologic analysis displayed that there was no statistical significance in BIC and CBa values between group I and the group II (P>.05), and RT/BIC and RT/CBa between group I and group II were statistically significant (P<.05). Conclusion: It is possible to obtain more substantial re-osseointegration within shorter periods than the period needed for the initial osseointegration in case of iatrogenically unscrewed implants.

• Journal of Genetic Medicine
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• v.6 no.1
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• pp.74-80
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• 2009

Purpose: To assess the value of first-trimester pregnancy-associated plasma protein-A (PAPP-A), nuchal translucency (NT) and second-trimester alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), unconjugated estriol (uE3), and inhibin-A in predicting pregnancy complications other than fetal aneuploidy. Materials and Methods: A retrospective study in 3,121 singleton pregnancies with integrated testing was performed at Kangnam CHA hospital between January 2005 and December 2006. Baseline characteristics, pregnancy outcomes, and serum marker levels were obtained by review of the medical records. We analyzed the data to identify associations between the integrated screening markers and adverse pregnancy outcomes. Statistical analyses were performed with the SPSS program. Results: In preterm labor and preeclampsia, high AFP, hCG, and inhibin-A levels and low PAPP-A and NT levels were found to be significantly correlated (P<0.05). Elevated second-trimester inhibin-A levels were associated with preeclampsia (odds ratio 2.843), low birth weight (odds ratio 1.446), and preterm labor (odds ratio 1.287), and while decreased first-trimester PAPP-A levels were associated with preeclampsia (odds ratio 0.51) and preterm labor (odds ratio 0.75). Conclusion: First- and second-trimester maternal serum markers screening can be used for predicting high-risk pregnancies.

• Journal of the Korean Society of Radiology
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• v.5 no.6
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• pp.401-407
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• 2011

The purpose of this study is to know the differences of MR spectra, obtained from normal volunteers by variable TE value, through the quantitative analysis of brain metabolites by peak integral and SNR between 1.5T and 3.0T, together with PRESS and STEAM pulse sequence. Single-voxel MR proton spectra of the human brain obtained from normal volunteers at both 3.0T MR system (Magnetom Trio, SIEMENS, Germany) and 1.5T MR system (Signa Twinspeed, GE, USA) using the STEAM and PRESS pulse sequence. 10 healthy volunteers (3.0T:3 males, 2 females; 1.5T : 3 males, 2 females) with the range from 22 to 30 years old (mean 26 years) participated in our study. They had no personal or familial history of neurological diseases and had a normal neurological examination. Data acquisition parameters were closely matched between the two field strengths. Spectra were recorded in the white matter of the occipital lobe. Spectra were compared in terms of resolution and signal-to-noise ratio(SNR), and echo time(TE) were estimated at both field strengths. Imaging parameters was used for acquisition of the proton spectrum were as follow : TR 2000msec, TE 30ms, 40ms, 50ms, 60ms, 90ms, 144ms, 288ms, NA=96, VOI=$20{\times}20{\times}20mm3$. As the echo times were increased, the spectra obtained from 3.0T and 1.5T show decreased peak integral and SNR at both pulse sequence. PRESS pulse sequence shows higher SNR and signal intensity than those of STEAM. Especially, Spectra in normal volunteers at 3.0T demonstrated significantly improved overall SNR and spectral resolution compared to 1.5T(Fig1). The spectra acquired at short echo time, 3T MR system shows a twice improvement in SNR compared to 1.5T MR system(Table. 1). But, there was no significant difference between 3.0Tand 1.5T at long TE It is concluded that PRESS and short TE is useful for quantification of the brain metabolites at 3.0T MRS, our standardized protocol for quantification of the brain metabolites at 3.0T MRS is useful to evaluate the brain diseases by monitoring the systematic changes of biochemical metabolites concentration in vivo.

• Research in Community and Public Health Nursing
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• v.5 no.1
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• pp.81-96
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• 1994

The primary purpose of this study was to identify factors affecting health promoting lifestyles of college students on the basis of Pender's Health Promotion Model. The subjects were 1,159 students of one university in Seoul. These data were collected by self reporting questionnaire from April 19 to May 3, 1993. This study examined health promoting lifestyles, cognitive-percep-tual factors: perceived health status, perceived importance of health, health locus of control, and health conception, and modifying factors: sex, grade, major, residence type, and attendance at a health care course. The instruments used in this study were Health Promoting Lifestyle Profile by Walker et al. (1987), Health Value Scale by Wallston et al. (1976), Health Locus of Control by Wallston et al. (1978), and Health Conception Scale by Laffrey(1986). The data were analyzed by Cronbach's $\alpha$, mean, standard deviation, percentage, t-test, ANOVA, Pearson's Correlation Coefficient, and Stepwise Multiple Regression with SPSS PC+ Program. The results were as follows : 1. The means of health promoting lifestyles revealed total 3.33, self actualization 3.74, health responsibility 2.72, exercise 2.80, nutrition 3.55, interpersonal surpport 3.76, and stress management 2.96. Interpersonal support showed the highest score and health responsibility showed the lowest score. 2. No significant differences between sex, grade, major, and residence type, and health promoting lifestyles Were founded(p>.05). Attendants at a health care course showed a significant higher score than nonattendants (p<.001). Male showed a significant higher score in exercise subscale, female showed significant higher scores in health responsibility, nutrition, interpersonal support, stress management subscales(p<.001), residence type showed a significant difference in nutrition subscale(p<.001). 3. No significant differences between perceived health status and sex, grade, major, residence type, and attendance at a health care course were founded(p>.05). Perceived importance of health showed no differences among sex, grade, major, and residence type(p>.05), showed only in attendance at a health care course (p<.001). Attendants at a health care course showed a significant higher score than nonattendants(p<.001). No significant differences between health conception and sex, grade, major, and residence type were founded (p>.05), only significant difference between health conception and attendance at a health care course was founded(p<.05). Nonattendants showed a significant higher score in clinical health conception, attendants showed a significant higher score in wellbeing health conception(p<.05). 4. A significant positive correlation between health promoting lifestyles and perceived health status was founded(r=.2415, p<.001). A significant positive correlation between health promoting lifestyles and perceived importance of health was founded (r=.1475, p<.001). The health promoting lifestyles revealed significant positive correlations in internal and powerful others locus of control (r=.3187, p<.001: r=.1475, p<.001), but revealed a significant negative correlation in chance locus of control(r=-.997, p<.001). A significant positive correlation between health promoting lifestyles and clinical health conception and wellbeing health conception were founded (r=.1241, p<.001 : r=.3047, p<.001). 5. Perceived health status was the highest factor predicting health promoting lifestyles of college students(R=.3415, $R^2=11.62$). Perceived health' status, perceived improtance of health, internal locus of control, wellbeing health conception, powerful others locus of control accounted for 28.19% in health promoting lifestyle patterns. In conclusion, college students who reported more helath promoting lifestyles evaluated their health positively, perceived importance of health highly, perceived their health as affected by theirselves, powerful others but not by chance or luck, and accepted health as high level wellness rather than merely the absence of illness. Those who attending at a health care course had healthier lifestyle patterns. And attendance at a health care course had significant. correlations in these cognitive-perceptual factors. Further studies are required to identify reasons of attending a health care course, and to compare health promoting lifestyles pre-post attending a course related to health care.