• Journal of Korean Society of Forest Science
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• v.12 no.1
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• pp.45-54
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• 1971

Ecological studies on the effect of an accidental fire on the composition of the post-fire vegetation in relation to the productivity system were made at the burned site on Mt. Samak located at Duckduwon-Ri, Sumyun, Chun Sung-Kun, Kangwon-Do, the same plots used in the previous study carried out in 1967. The result are summarized as follows. 1. In the productivity system, the standing crop measured was as follows; Carex Lanceolata var. Nana, Miscanthus purpurscens etc. were contained in the herbs and their individual number was larger than that of the woody plants. (Table 1). In the woody plants, Quercus Acutissima was the most abundant, showing larger number of tree than Quercus dentata. The S.D.R. value of the family Poaceae was the highest among the herbs and in the test plots, it was 4 times larger in number than in the controlled plots. (Table 3, Fig. 4, 5). 2. In the unburned sities, 5 dominant species were selected and by calculating their S.D.R., it was shown that woody plants, S.D.R. is 4.43 while it is 11.52 with herbs. (Table 4, Fig. 6). 3. When making comparisons with the standing crop on the higher around, it was found that the test plots had 522.45 gm more than the controlled and 1470. 53gm more than those on lower ground. These results were considered to indicate that high temperature caused by fire resulted in the increase of germination rate of seeds as it was seen in the previous study and it further stimulate the growth of the perennial plants. (Table 6, 7) 4. In the number of species, the standing crop was increased in the order of Genus Miscanthus and Genus Carex. and in the woody plants Genus Lespedeza was increased in the standing crop. 5. It was found that in the rest plots, total summed height was greater by about 6000cm than that in the controlled plots. 6. In conclusion, the forest fire gave a great loss to tall trees and woody plants burning them together with unmatured seeds. In the succession of the 2nd year it was considered that the growth of the perennial plants had been stimulated on the barned sites.

• Korean Journal of Dental Materials
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• v.45 no.4
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• pp.243-256
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• 2018

The purpose of this study was to investigate the effects of the anodization and cyclic calcification treatment on the surface characteristic and bioactivity of the titanium thin sheet in order to obtain basic data for the production of bioactive titanium membrane. A $30{\times}20{\times}0.08mm$ titanium sheets were prepared, and then they were pickled for 10 seconds in the solution which was mixed with $HNO_3:HF:H_2O$ in a ratio of 12: 7: 81. The $TiO_2$ nanotube layer was formed to increase the specific surface area of the titanium, and then the cyclic calcification treatment was performed to induce precipitation of hydroxiapatite by improvement of the bioactivity. The corrosion resistance test, wettability test and immersion test in simulated body solution were conducted to investigate the effect of these surface treatments. The nanotubes formed by the anodization treatment have a dense structure in which small diameter tubes are formed between relatively large diameter tubes, and their inside was hollow and the outer walls were coupled to each other. The hydroxyapatite precipitates were well combined on the nanotubes by the penetration into the nanotube layer by successive cyclic calcification treatment, and the precipitation of hydroxyapatite tended to increase proportionally after immersion in simulated body solution as the number of cycles increased. In conclusion, it was confirmed that induction of precipitation of hydroxyapatite by cyclic calcification treatment after forming the nanotube $TiO_2$ nanotube layer on the surface of the titanium membrane can contribute to improvement of bioactivity.

• Journal of the Korean Child Neurology Society
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• v.26 no.4
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• pp.227-232
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• 2018

Purpose: Febrile seizure (FS) is the most common type of seizure in children between 6 months to 5 years of age. A family history of febrile seizures can increase the risk a child will have a FS. Yet, prevalence of FS regarding external environment has not been clearly proved. This study attempts to determine the association between prevalence of FS and weather. Methods: This study included medical records from the Korea National Health Insurance Review and Assessment Service. Data were collected from 29,240 children, born after 2004, diagnosed with FS who were admitted to one of the hospitals in Seoul, Korea, between January 2009 and December 2013. During the corresponding time period, data from the Korea Meteorological Administration on daily monitoring of four meteorological factors (sea-level pressure, amount of precipitation, humidity and temperature) were collected. The relationships of FS prevalence and each meteorological factor will be designed using Poisson generalized additive model (GAM). Also, the contributory effect of viral infections on FS prevalence and weather will be discussed. Results: The amount of precipitation was divided into two groups for comparison: one with less than 5 mm and the other with equal to or more than 5 mm. As a result of Poisson GAM, higher prevalence of FS showed a correlation with smaller amount of precipitation. Smoothing function was used to classify the relationships between three variables (sea-level pressure, humidity, and temperature) and prevalence of FS. FS prevalence was correlated with lower sea-level pressure and lower humidity. FS prevalence was high in two temperature ranges (-7 to $-1^{\circ}C$ and $18-21^{\circ}C$). Conclusion: Low sea-level pressure, small amount of precipitation, and low relative air humidity may increase FS prevalence risk.

• Korean Journal of Social Welfare Studies
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• v.48 no.3
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• pp.171-208
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• 2017

The purpose of this study is to classify the underlying and parsimonious types of child maltreatment and examine whether the effects of risk factors on child maltreatment recurrence differ by type of maltreatment. We utilized the multiyear national administrative data from the National Child Maltreatment Information System collected by Child Protection Agency in Korea. Of 26,921 child maltreatment victims reported and substantiated on or after January 1, 2012, 1,447 children who had recurrence of child maltreatment until December 31, 2015 were selected as maltreatment recurrence group and 4,580 children who had not experienced maltreatment since first substantiation were assigned as maltreatment non-recurrence group. Latent class analysis(LCA) and latent transition analysis(LTA) were used to group children with similar maltreatment subtypes into discrete classes of child maltreatment recurrence. Logistic regression is employed to examine the association between the child maltreatment predominant types and risk factors for recurrence. Results of LCA and LTA showed four latent classes representing predominant type of child maltreatment: 'physical abuse predominant type', 'emotional abuse predominant type', 'sexual abuse predominant type', and 'neglect type'. Significant differences in the effect of risk factors among latent classes were found in child's age and gender, perpetrator's gender, family poverty, biological parent as the perpetrator, domestic violence toward partner, perpetrator's alcoholic problem, insufficient parenting skills, and out-of-home care service, Based on these findings, results suggested how the typology can be used to guide decision about who to target in prevention and intervention programs, and which features of risk factors to target. Practice and policy implications as well as further research tasks were discussed in the lights of searching for useful and important strategies to prevent recurrence of child maltreatment.

• Korean Journal of Social Welfare Studies
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• v.47 no.1
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• pp.29-56
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• 2016

The purpose of this study is first, to explore the level of codependency among social work related professionals since codependency of professionals in the field has not been explored much in Korea. Second purpose is to examine whether codependency affects the level of burnout. Last purpose is to examine moderating effects of the Sex-role attitude on the relationship between codependency and burnout. Data were collected from the 11th of December in 2014 until the 28th of February in the following year. Self-administered questionnaires were distributed to care professionals practicing in social work institutions in Daejeon City and Choongcheong province, via email and mail. In addition, surveys were administered at several continuing education training venues. Instruments used for this study include CODAT(Codependency Assessment Tool) developed by Hughes-Hammer and colleagues in 1998, MBI(Maslach Burnout Inventory) developed by Maslach and Jackson in 1981, and SRA(Sex Role Attitude) developed by Osmond and Maryin in 1975. In total, 368 surveys were used for final analysis. The results include that gender did not have statistically significant relationship with the overall codependency, however, male showed statistically higher score than female in one of subscales of codependency called hiding oneself. Workers in the residential settings showed higher level of codependency than those in non-residential settings, especially in the subscale of Other focus or Self-neglect. Codependency showed a strong relationship with Burnout. Among the five-factor structure of the CODAT, Medical problem, Low Self-worth and Family of Origin showed strong relationship with the Burnout score. And the moderating effects of Sex-role Attitude showed a statistically significant relationship between codependency and burnout. Conservative sex-role attitude amplified the level of burnout on the relationship between codependency and burnout. Based on the result, educational and policy implications were made in order to prevent burnout among social work related professionals.

• Korean Security Journal
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• no.57
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• pp.57-84
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• 2018

This study assumes that the perception of the ex-prisoner's against stigma will affect trust in interpersonal relationship. Prior studies have suggested that there is a stigma at the base of the awareness where people avoid and discriminate against ex-prisoner's. This in turn affects ex-prisoner's' recividicism, but there is no study about ex-prisoner's perception of stigma in Korea. Although stigma can be explained in numerous ways, this study is based on the opinion of Phillips(2016), which divides the subscale of stigma as perceived public stigma, perceived personnel stigma, and self stigma. He insisted that ex-prisoner's believe perceived public stigma higher than self-stigma. these results are consistent with this study. However, it is important to note that although ex-prisoner's are more aware of public stigma than self-stigma, they are actually more influenced by self stigma in pereonal relationships. This means that ex-prisoner's are more susceptible to internal psychological awareness than external social recognition. Therefore, the development and intervention of the program to overcome the internal self-stigma of the released prisoner is required. In this study, first, stigma, especially self-stigma turned out to have influence on the interpersonal trust. Therefore, as self-stigma level increased, the interpersonal trust decreased in most cases. Second, it was shown that stigma has the greatest influence on children out of family members, co-workers out of social relationship, self trust out of general relationship in. This confirms that stigma is a factor that greatly influences relationship between important people for ex-prisoner's. Third, since self-sigma negatively reestablish self-identity, make individuals recognize themselves as deviators and show bad lifestyle, which lead them to become habitual offender, ex-prisoner's need to make efforts to overcome self-stigma, and development and intervention of program that can make ex-prisoner's have positive self identity is requested. Fourth, although participants in the study were only male, it seems that there is difference in recognition of stigma by gender, and influence of stigma not only on interpersonal relationships, but also on social reintegration and recidivism imply that these might be good future research topics.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.847-852
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• 2011

Green manure crops are mainly used to reduce the application of chemical fertilizers. Mixture of green manure crops have beneficial effects in agroecosystem. In this study, experiments were conducted to evaluate the effects of monoculture and mixtures of crimson clover (Trifolium incarnatum) on rice growth and yield in paddy. This experiment was conducted at Sinheung series (fine loamy, mixed, nonacid, mesic family of Fluvaquentic Endoaquepts) from Oct. 2007 to Oct. 2009 at the National Institute of Crop Science (NICS), RDA, Suwon, Gyeonggi province, Korea. Seeding rates of crimson clover (CC) were consisted of monoculture (CC2, 3, 4 kg and hairy vetch 5 kg $10a^{-1}$) and mixtures (CC 2 + barley 7, CC 3 + barley 7, CC 4 + barley 7, and CC2 + hairy vetch $5kg\;10a^{-1}$). Seeds were drilled by partial tillage machine on 9th Oct. in 2007. Monoculture and mixture of crimson clover as a green manure crop was incorporated in soil for rice cultivation on 15th May in 2008. Chemical fertilizers had not been applied to monoculture and mixture plots. The biomass and N production of monoculture plots were lower than mixture plots. The biomass and N production of CC 2 + hairy vetch $5kg\;10a^{-1}$ plot were the highest among mixtures treatments. In rice growing season, ammonium nitrogen concentrations in soil were a little high trends at CC 2 + hairy vetch $5kg\;10a^{-1}$ plot. And soil bulk density and porosity were improved at mixture plot after rice harvesting. The rice yield of CC 2 + hairy vetch $5kg\;10a^{-1}$ plot was not significantly different from conventional practice plot. These results indicated that cropping of crimson clover with hairy vetch mixture was better than barley mixture for environmental friendly rice cultivation.

• Journal of Nutrition and Health
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• v.52 no.3
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• pp.250-257
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• 2019

Purpose: Aster glehnii (AG) and Aster yomena (AY) are medicinal plants that belong to the family Compositea and grow widely in Korea. Plants in the genus Aster have been used to treat snakebite wounds or bruises in oriental medicine. This study compared the effects of anti-oxidants and anti-adipocyte differentiation according to the species (the aerial parts of AG and AY). Methods: AG and AY were extracted using 70% ethanol (-E) and water (-W) at room temperature. The anti-oxidant activities were measured by total phenol contents (TPC), total flavonoid contents (TFC), DPPH and $ABTS^+$ assay. In addition, correlation analysis was performed for the anti-oxidant compounds and effect. The level of anti-adipocyte differentiation was assessed using an oil red O assay on pre-adipocytes. Results: AG-W showed higher TPC ($6.92{\mu}g/mL$) and AG-E presented higher TFC ($8.22{\mu}g/mL$) than the other extracts. Furthermore, AG-E exhibited higher radical scavenging activity in the DPPH and $ABTS^+$ assay ($IC_{50}$: 104.88 and $30.06{\mu}g/mL$). In the cytotoxicity assay, AG and AY extracts at concentrations less than $100{\mu}g/mL$ were non toxic. AG-W reduced the lipid accumulation of 3T3-L1 cells significantly after differentiation (70.49%) compared to the other extracts. Conclusion: These results show that the water extract of AG has anti-oxidant effects and reduces the differentiation of 3T3-L1 cells. Therefore, AG has utility as a functional food material for its anti-oxidant activities and ability to prevent lipid accumulation.

• Journal of Life Science
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• v.31 no.2
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• pp.199-208
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• 2021

Euonymus porphyreus, a species of plant in the Celastraceae family, is widely distributed in East Asia, especially in Southern China. The botanical characteristics of E. porphyreus have been reported, but its antioxidative and anticancer activities remain unclear. In this study, we evaluated the antioxidative and anticancer effects of ethanol extracts of E. porphyreus (EEEP) and the molecular mechanism of its anticancer activity in human lung adenocarcinoma A549 cells. The total polyphenol and flavonoid compound contents from EEEP were 115.42 mg/g and 23.07 mg/g, respectively. EEEP showed significant antioxidative effects with a concentration at 50% of the inhibition (IC50) value of 11.09 ㎍/ml, as measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. EEEP showed cytotoxic activity by increasing the SubG1 cell population of A549 cells in a dose-dependent manner. Apoptosis in A549 cells treated with EEEP was evident due to increased apoptotic cells and apoptotic bodies, as detected by Annexin V and 4,6-diamidino-2-phenylindole (DAPI) staining, respectively. EEEP-induced apoptosis resulted in increased expression of the First apoptosis signal (Fas), p53, and Bax, with decreased expression of Bcl-2 and subsequent activation of caspase-8, -9, and caspase-3, leading to cleavage of poly (ADP-ribose) polymerase (PARP). Collectively, these results suggest that EEEP may exert an anticancer effect by inducing apoptosis in A549 cells through both intrinsic and extrinsic pathways.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.29 no.4
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• pp.1-13
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• 2011

The purpose of this study is to consider practical examples of the method of utilizing plant material 'lotus' used by the ancients, and the value and meaning they wanted to get from it. The method of this study to do this is descriptive study to consider and interpret poem and painting reflecting impression and concept world of lotus. Summary of this study is as follows. First, ornamental value of lotus could be divided in effect of group plant and detail value held by the flower, the leaves and the stem. Especially, group plant lotus in large site provides unique landscape differentiated form other flowering plants. As well, another feature of lotus is its high ornamental value spread in detail elements including the flower, the leaves, the stem and the lotus seed. Second, fragrance expressed 'Hyang-won-ik-cheong(香遠益淸)' is an important charm of lotus. Lotus was utilized as olfactory element providing fragrance. The ancients considered lotus fragrance not only for enjoy but as symbolic object comparing noble man's dignity so that they expressed it in poem and painting. Third, lotus was utilized as acoustical element. That is, the sound of raindrops harmonizing the surface of water and wide lotus leaves was called 'hearing lotus fond and rain', enjoying it as classic grace. Fourth, summer play lotus sightseeing was called mind wash up meaning 'washing the mind polluted by the mundane world'. Such poetic taste was widely enjoyed by various classes from general public to royal family. Besides, poetic taste related with lotus is the method of drinking alcohol using the feature of big lotus leave and vacant stem, called 'Beog-tong-ju(碧筒酒)'. And in the Joseon dynasty period, when the distinction between the man and the woman influenced by Confucian, lotus seed and 'lotus collecting song' was important sign to express romance between man and woman. Lotus has been enamored by wide classes transcending cultural background as thought and religion since ancient times. Due to such reasons, various symbolic meaning of lotus and planting examples related to religious facilities as temples could not be considered in various manner is limitation of this study, and which is research project for the future.