• Korean Journal of Plant Taxonomy
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• 제47권3호
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• pp.222-235
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• 2017

A comparative study of the leaf epidermal micromorphology in the tribe Neillieae (Neillia: 4 species, 4 varieties; Physocarpus: 5 species; Stephanandra: 2 species) was carried out using scanning electron microscopy in order to evaluate the taxonomic and systematic implications of these characteristics. The leaves of the genera Neillia and Stephanandra were hypostomatic, whereas those of P. monogynus, P. opulifolius were amphistomatic. The range of the size of the stomata is $12.02-34.39{\times}10.76-27.13{\mu}m$; the smallest was found in N. thyrsiflora (average $13.98{\times}12.43{\mu}m$; $L{\times}W$), while the largest was measured in N. gracilis (average $26.82{\times}20.67{\mu}m$; $L{\times}W$). Paracytic stomata complexes are only found in N. affinis, and the anomocytic type was most commonly found. The papillate epidermal cell type was only observed on the abaxial surfaces of P. insularis. Platelet epicuticular waxes were found on the adaxial surfaces of N. affinis and S. tanakae. Four types (unicellular non-glandular, two- to five-armed, stellate, and glandular) of trichomes were found on the leaves. Stellates were observed in all species of Physocarpus except for P. insularis. Consequently, leaf epidermal micromorphological characteristics (e.g., the presence of papillate epidermal cells and stellate, and stomata complexes) may have high taxonomic and systematic value in Neillieae. Our results strongly support previous molecular phylogenetic and palynological hypotheses that Stephanandra and Neillia are a single genus and that Physocarpus insularis should be considered as a member of Spiraea.

• Korean Journal of Plant Taxonomy
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• 제48권2호
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• pp.143-152
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• 2018

A comparative study of leaf epidermal microstructures in genus Aruncus (two species, five varieties) was carried out using scanning electron microscopy in order to evaluate their significance in terms of taxonomy. All of the leaves of the taxa studied here were amphistomatic with undulate anticlinal walls, and smooth and flat periclinal walls on both surfaces. The size range of the stomata complex is $8.95-21.97{\times}7.50-16.99{\mu}m$: the largest one was found in Aruncus dioicus var. astilboides (average $18.01{\times}13.47{\mu}m$) and the smallest was measured and determined to be A. gombalanus (average $11.11{\times}8.94{\mu}m$). An anomocytic stomata complex was found in all of the studied taxa. The stomatal frequency on average was $27.54/0.05mm^2$; it is highest in A. gombalanus ($60.4/0.05mm^2$) and lowest in A. dioicus var. acuminatus ($11.6/0.05mm^2$). Two types (short stalked capitate glandular trichome and non-glandular trichome) of trichomes are found in the leaves. The non-glandular trichome was divided into three types based on the presence and degree of development of subsidiary cells. Anomocytic stomata of the hypostomatic type and the distribution pattern of capitate glandular trichomes were the major characters in this genus. The stomata size and frequency, the epidermal cell structure, the trichome type and the distribution pattern may have diagnostic importance among the taxa in the genus. Our leaf micromorphological results provide useful information for the taxonomic revision of the genus Aruncus.

• The Journal of the Petrological Society of Korea
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• 제25권3호
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• pp.241-252
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• 2016

In this paper, in order to test the possibility of applying K feldspar $pIR-IRSL_{290}$ signal(read out at $290^{\circ}C$) to date old terrace sediments(up to ~ 200 ka, MIS 7) in Korea, we investigated luminescence properties of $pIR-IRSL_{290}$ signals in K feldspar extracts from 27 marine and fluvial terrace sediment samples, and these were compared with those of quartz OSL and conventional K feldspar $IRSL_{50}$ (readout at $50^{\circ}C$) signals. The averaged $2D_0$ value of K feldspar $pIR-IRSL_{290}$ growth curves was ~ 700 Gy, which is consistent with that of $IRSL_{50}$ signal, and this is 3 times higher than that for quartz OSL (~ 250 Gy) on average. Where possible, K feldspar $pIR-IRSL_{290}$ ages were compared with quartz OSL and conventional $IRSL_{50}$ ages. Our preliminary K feldspar $pIR-IRSL_{290}$ ages were older than quartz OSL ages by about 200%, while fading rate-corrected conventional $IRSL_{50}$ ages are in good agreement with those based on quartz OSL. This seems to indicate the possibility of K-feldspar $pIR-IRSL_{290}$ age overestimation due to the presence of unbleachable $pIR-IRSL_{290}$ signals, even with a prolonged exposure to sunlight. Both quartz OSL and K-feldspar $pIR-IRSL_{290}$ signals for the samples from Noeum fluvial terrace and Gusan fault site were all in dose saturation level, thus unable to estimate the formation ages of the sediments. However, $2D_0$ values derived from the dose response growth curves strongly indicate that the Noeum fluvial terrace sediments have formed before 109-140 ka, while the fluvial sediments from Gusan fault were desposited before 100-105 ka. Further, this seems to suggest that the previous quartz OSL ages of ~40-50 ka for Gusan fault sediments should be the underestimated ones due to dose saturation problem.

• Korean Journal of Plant Resources
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• 제12권4호
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• pp.312-323
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• 1999

External morphology, principal component analysis, cluster analysis, and vegetation were investigated to understand the taxonomic relationships and native environmental characters of Megaleranthis saniculifolia populations in four different habitats. Morphological characters such as calyx length and width, calyx index, presence or absence of serrate in calyx lobe, length of peduncle, branch of peduncle and fruit characters were useful for the identification of four different habitats. But, characters of plant height, bract and seed in four habitats were similar. The results obtained based on the principal component(PC) analysis of treated 96 OTU were divided into two groups by PC 1, 2, 3, and the sums of contributions for the total variance were 66.79%(PC1 31.3%, PC2 20.7%, PC3 15.8%, respectively), and only Mt. Taeki population was distinctly different from populations of other three habitats. In cluster analysis based on average linkage cluster analysis and Ward's method, there were similarities in the composition of clustered taxa, and each populations were not identified. Importance value by relative coverage and frequency appeared in M. saniculifolia(50.81%), Aruncus dioicus(12.64%), Corydalus turtschanovii(11.62%), Veratrum oxysepalum(11.45%), Anemone koraiensis(8.96%), Meehania urticifolia(8.76%), Filipendula palmata(7.06%), Aconitum pseudo-laeve(5.66%), Pseudostellaria palibiniana(5.45%) and Smilacina japonica(5.25%), respectively. These species were considered to be highly similar with M. saniculifolia. The highest importance value in all investigated sites was M. saniculifolia, but specific composition of high level different from each habitat. Average diversity of species was 1.40, and the highest in Mt. Kwangdeok(1.31), lowest in Mt. Jumbong(1.17). Average soil pH was 5.25 and similar in each habitat. Although the lowest content of K ion, but the highest the EC, water capacity, organic compound, Ca content were found in soil of Mt. Sobaek. Soils in Mt. Kwangdeok had the lowest content of EC, organic compound, Ca. Soils of Mt. Jumbong showed the highest of Mg content, but the lowest of water capacity, $P_2O_5$, and K contents.

• Journal of Soil and Groundwater Environment
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• 제14권4호
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• pp.23-32
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• 2009

The sorption of europium (Eu (III)) onto kaolinite and the influence of humic acids over a range of pH 3 ~ 11 has been studied by batch adsorption experiment (V/m = 250 : 1 mL/g, $C_{Eu(III)}\;=\;1\;{\times}\;10^{-5}\;mol/L$, $C_{HA}\;=\;5{\sim}50\;mg/L$, $P_{CO2}=10^{-3.5}\;atm$). The concentrations of HA and Eu(III) in aqueous phase were measured by UV absorbance at 254nm (e.g., $UV_{254}$) and ICP-MS after microwave digestion for HA removals, respectively. Results showed that the HA sorption onto kaolinite was decreased with increasing pH and their sorption isotherms fit well with the Langmuir adsorption model (except pH 3). Maximum amount ($q_{max}$) for the HA sorption at pH 4 to 11 was ranged from 4.73 to 0.47 mg/g. Europium adsorption onto the kaolinite in the absence of HA was typical, showing an increases with pH and a distinct adsorption edge at pH 3 to 5. However in the presence of HA, Eu adsorption to kaolinite was significantly affected. HA was shown to enhance Eu adsorption in the acidic pH range (pH 3 ~ 4) due to the formation of additional binding sites for Eu coming from HA adsorbed onto kaolinite surface, but reduce Eu adsorption in the intermediate and high pH above 6 due to the formation of aqueous Eu-HA complexes. The results on the ternary interaction of kaolinte-Eu-HA are compared with those on the binary system of kaolinite-HA and kaolinite-Eu and adsorption mechanism with pH was discussed.

• The Journal of Korean Society for School & Community Health Education
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• 제4권
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• pp.117-139
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• 2003

The purpose of this research lies in presenting logical viability for the measures that curtail access to lewd Internet contents by middle school students amidst the reality in which lewd contents are circulated freely through the Internet, a medium that the middle school students find most easy to access. In order to establish right form of awareness towards sex, this research identified the ways they access the lewd Internet contents, their reaction after the exposure to those contents, their knowledge of sex, their concerns regarding sex and their accessibility to sexual activities in order to conduct a comparative analysis on the relationship between lewd Internet contents and their awareness of sex. First, realities of accessing lewd Internet contents and reactions according to the demographics of middle school students There isa significant difference in the experience of accessing lewd Internet contents in terms of gender. Mostly, male students tend to access the contents more. As for the way they access the lewd Internet contents, both male and female students replied that they access through spam mail of lewd nature. Thus, measures to address this problem are needed urgently. As to when they first accessed the lewd contents, most of the research subjects replied that they accessed either in elementary school period or in the early middle school period. This shows that most of the students got exposed to lewd contents even before they could establish positive, correct awareness of sex. Thus, there is a risk that they may formulate wrong kind of sexual awareness. Accordingly, it is necessary to develop measures through focused sex education. Students are divided into two groups according to the time they spend on the contents averagely: those who spend over one hour and those who spend less than an hour on the lewd contents. If the students spending longer hours are not to be checked and properly guided, it may lead to increasing cases of sexual delinquencies due to their wrongly formed awareness of sex. When the question of existence(non-existence) of guardian was addressed, students with both parents tend to access the lewd Internet contents in a more diverse manner and tend to access more compared to those students from single parent or no-parent families. Accordingly, guardians need to pay attention to how their children are using the Internet. Second, awareness of sex depending on the middle school students' demographics In case of sexual knowledge, middle school students shows relatively high level of knowledge. In particular, female students are found more knowledgeable than male students, and the students in upper years are more knowledgeable as well. As a result, this research recommends that the students in lower years should be guided with more basc and detailed information, while those in upper years need to be taught to form and express their own thoughts and attitudes and to build up independence on this matter. In case of worries about sex, both male and female students don't worry too much about it. However, male students are more concerned about sex than female students in a more diverse ways. As for the differences by academic year, concerns for sex increase, as students get older. Accordingly, sex education that helps establish sound perception of the opposite sex and that focuses on the etiquettes that one must adhere to at the presence of the opposite sex need to be conducted against middle school students. In case of accessibility to sex, male students manifest higher tendency than female students. As for the differences by academic year, those in the first and second years show higher accessibility than those in their third year. In general, younger students tend to be more open-minded toward sex. Accordingly, students in lower academic years need to undergo basic knowledge oriented sex education, whereas those in upper academic years need to undergo discussion centered sex education where they subject to questions regarding their attitude and opinion. Third, relationship between the reactions after the exposure to the lewd Internet contents and their awareness of sex As the frequency of contact with lewd Internet contents increases, awareness of sex increases as well. Thus, the lewd Internet contents contribute to the increase in students' concern for sex as well as increase in accessibility to sex, which eventually become barriers to students' establishment of a healthy perception of sex. Reactions to sex after the exposure to lewd Internet contents and awareness of sex indicate a significant correlation. However, negative correlation is manifested with knowledge of sex. Thus, it is possible to know that the greater access to lewd Internet contents does not necessarily translate into increase in knowledge of sex. However, the study showed there is a correlation between concerns for sex and the level of accessibility to sex. In more detail, the more reactions to the contents they show, the more concerns for sex they have and the more positively they take acceptability to sex. Moreover, it is necessary to develop necessary measures since textbooks today do not include measures needed to address the lewd Internet contents. Given the above findings, it is necessary to continue to complement structural measures in order to prevent easy access of lewd Internet contents by middle school students. Moreover, it is necessary to be considerate of the students so that they themselves can form a healthy Internet culture and grow up within positive framework for the sex education.

• Korean Journal of Soil Science and Fertilizer
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• 제32권4호
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• pp.383-397
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• 1999

For sites to be investigated, the results of such an investigation can be used in determining foals for cleanup, quantifying risks, determining acceptable and unacceptable risk, and developing cleanup plans t hat do not cause unnecessary delays in the redevelopment and reuse of the property. To do this, it is essential that an appropriately detailed study of the site be performed to identify the cause, nature, and extent of contamination and the possible threats to the environment or to any people living or working nearby through the analysis of samples of soil and soil gas, groundwater, surface water, and sediment. The migration pathways of contaminants also are examined during this phase. Key aspects of cost-effective site assessment to help standardize and accelerate the evaluation of contaminated soils at sites are to provide a simple step-by-step methodology for environmental science/engineering professionals to calculate risk-based, site-specific soil levels for contaminants in soil. Its use may significantly reduce the time it takes to complete soil investigations and cleanup actions at some sites, as well as improve the consistency of these actions across the nation. To achieve the effective site assessment, it requires the criteria for choosing the type of standard and setting the magnitude of the standard come from different sources, depending on many factors including the nature of the contamination. A general scheme for site-specific assessment consists of sequential Phase I, II, and III, which is defined by workplan and soil screening levels. Phase I are conducted to identify and confirm a site's recognized environmental conditions resulting from past actions. If a Phase 1 identifies potential hazardous substances, a Phase II is usually conducted to confirm the absence, or presence and extent, of contamination. Phase II involve the collection and analysis of samples. And Phase III is to remediate the contaminated soils determined by Phase I and Phase II. However, important factors in determining whether a assessment standard is site-specific and suitable are (1) the spatial extent of the sampling and the size of the sample area; (2) the number of samples taken: (3) the strategy of taking samples: and (4) the way the data are analyzed. Although selected methods are recommended, application of quantitative methods is directed by users having prior training or experience for the dynamic site investigation process.

• Korean Journal of Psychosomatic Medicine
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• 제24권2호
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• pp.191-199
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• 2016

Objectives : Despite the increased popularity of highly caffeinated beverages, there is little research examining psychiatric adverse effects. The purpose of this study was to investigate the relationships among pattern of highly caffeinated beverage intake and depressive symptom, suicidal ideation, suicidal plan, suicidal attempt in Korean adolescents. Methods : The data was obtained from the 2014 Korean Youth's Risk Behavior Web-based Study by Korea Centers for Disease Control & Prevention. All participants conducted web-based questionnaire survey. Chisquare test and multiple logistic regression analysis were performed to determine the association among highly caffeinated beverage intake pattern, depressive symptom, suicidal ideation, suicidal plan and suicidal attempt adjusting for differences in age, gender, academic achievement, socioeconomic status. Results : A total of 71,638 participants were enrolled in this study. Depressive symptom, suicidal ideation, suicidal plan and suicidal attempt were significantly more frequent in the group with presence of highly caffeinated beverage intake within 1 week than in non-drinker group(p<0.01). Highly caffeinated beverage intake was significantly associated with suicidal attempt(OR=1.99 ; 95% CI, 1.77-2.22). In addition, depressive symptom, suicidal ideation, suicidal plan and suicidal attempt were significantly more common in the group with heavy-drinker who exceed recommended daily intake dose of caffeine than in the group with light-drinker(p<0.01). Heavy drinking of caffeinated beverage was significantly associated with suicidal attempt(OR=4.05 ; 95% CI, 3.02-5.43). Conclusions : We found that highly caffeinated beverage intake was related to more frequent depressive symptom, suicidal ideation, plan, attempt in adolescents. Also, caffeine intake which exceed recommended daily intake dose identified the predictor of suicidal attempt. Our result suggested that clinicians need to be aware of the possible psychiatric adverse effects of highly caffeinated beverage in vulnerable population including young adolescents.

• Korean Journal of Psychosomatic Medicine
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• 제24권2호
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• pp.208-216
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• 2016

Objectives : According to the recent Korean National Police Agency report, rape victims were 17.1%, but sexual molestation victims were more than the rape victims by 78.0%. Despite many international reports about the occurrence of severe psychiatric symptoms in sexual molestation victims, there is no domestic research. Therefore in this study, we investigated psychiatric symptoms of sexual molestation victims, and we also compared it with psychiatric symptoms in rape victims. Methods : 58 women who visited Busan Smile Center within 3months after sexual violence were the study subjects. Questionnaire about sociodemographic and sexual violence related characteristics were retrospectively investigated. Of the psychiatric symptoms, Beck Depression Inventory(BDI), Beck Anxiety Inventory(BAI) for severity of depression and anxiety, and Impact of Event Scale-Revised(IES-R) to check the presence of posttraumatic stress disorder(PTSD) symptoms were used. Results : Of 58 sexual violence victims, sexual molestation victims were 36(62.1%) and rape victims were 22(37.9%). In sexual molestation victims, 80.6% had more than moderate severity of depression, 83.3% had more than moderate severity of anxiety, and 94.4% had significant scores at PTSD screening test. Compared with rape victims' psychiatric symptoms(each 95.5%, 95.5%, 95.5%) there were no significant difference. Conclusions : The majority of sexual molestation victims were also accompanied by depression, anxiety and PTSD symptoms as rape victims. There results suggest that appropriate assessment and early treatment for psychiatric symptom must be made in the early stage of injury in sexual molestation victims.

• Korean Journal of Psychosomatic Medicine
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• 제24권2호
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• pp.184-190
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• 2016

Objectives : This study analyzed the differences of body mass index(BMI) in Korean patients with Alzheimer's diseases(AD), Mild Cognitive Impairment(MCI), and healthy controls to verify whether low BMI is associated with cognitive impairment. Furthermore, this study also sought to examine any association between BMI and Mini Mental State Examination-Korean version(MMSE-K), Clinical Dementia Rating(CDR), and Global Deterioration Scale(GDS). Methods : A total of 257 subjects were included in the study. History taking, mental status examination, physical examination and neurocognitive function test were carried out for the diagnosis of AD and MCI. The subjects' demographic data and presence of diseases were also surveyed. The overall cognitive function and severity of diseases were assessed using MMSE-K, GDS, and CDR. Results : The order of BMI was found to be healthy controls>MCI>AD, with statistically significant differences among the groups. The order of MMSE-K scores was similar, with healthy controls>MCI>AD in statistically significant differences. The healthy controls had the lowest CDR and GDS scores, and AD patients had the highest scores. There was a significant positive correlation between BMI and MMSE scores(r=0.238, p=0.000). BMI was negatively correlated with CDR(r=-0.174, p=0.008) as well as with GDS(r=-0.233, p= 0.000). Conclusions : Measuring BMI of patients with AD or MCI is expected to be meaningful in that BMI could be a clinical indicator of AD. We expect this to be beneficial for the diagnosis, prevention, and therapeutic approach of AD and also expect large-scale, long-term longitudinal studies to follow.