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Environmental Change of High Moor in Mt. Dae-Am of Korean Peninsula (대암산 고층습원의 환경변천)

  • Yoshioka, Takahito;Kang, Sang-Joon
    • Korean Journal of Ecology and Environment
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    • v.38 no.1 s.110
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    • pp.45-53
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    • 2005
  • The environmental change of Yong-nup in Mt. Dae-Am, which is located at the northern part of Kangwon-Do, Korea, was assesed with peat sedimentary carbon and nitrogen isotope analysis. The surface layer of the peat (0 ${\sim}$ 5 cm) was 190 year BP, and the middle layers (30 ${\sim}$ 35 cm and 50 ${\sim}$ 55 cm) were 870 year BP and 1900 year BP, respectively. Bulk sedimentation rate was estimated to be about 0.4 mm $year^{-1}$ for 0 cm to 30 cm and 0.15 mm $year^{-1}$ for 35 cm to 50 cm. The $^{14}C$ age of the bottom sediment (75 ${\sim}$ 80 cm) collected and measured in this study was about 1900 year BP, although it was measured that the $^{14}C$ of the lowest bottom sediment in Yong-nup was 4105 ${\pm}$ 175 year BP (GX-23200). Since the $^{14}C$ ages for 50 ${\sim}$ 55 cm and 75 ${\sim}$ 80 cm layers were almost the same as 1890 ${\pm}$ 80 fear BP (NUTA 5364) and 1850 ${\pm}$ 90 year BP (NUTA 5462), respectively, we have estimated that the deep layers (55 ${\sim}$ 80 cm) in the high moor were the original forest soil. The low organic C and N contents in the deeper layers supported the inference. The sediment of 50 ${\sim}$ 55 cm layer contains much sandy material and showed very low organic content, suggesting the erosion (flooding) from the surrounding area. In this context, the Yong-nup, high moor, of Mt. Dae-Am, might have developed to the sampling site at about 1900 year BP. The ${\delta}^{13}C$ values of organic carbon and the ${\delta}^{15}N$ values of total nitrogen in the peat sediments fluctuated with the depths. The profile of ${\delta}^{13}C$ may indicate that the Yong-nup of Mt. Dae-Am have experienced the dry-wet and cool-warm period cycles during the development of the high moor. The ${\delta}^{15}N$ may indicate that the nitrogen cycling in the Yong-nup have changed from the closed (regeneration depending) system to the open (rain $NO_3\;^-$ and $N_2$ fixation depending) system during the development of the high moor.

The delousing of head louse in primary schools and kindergartens established as an annex to the primary school in Namwon-shi, Jollabuk-do, Korea(1995) (남원시 초등학생 및 병설유치원생의 머릿니 구제사업(1995))

  • Lee, Kyu-Jae;Ahn, Yung-Kyum
    • Journal of agricultural medicine and community health
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    • v.22 no.1
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    • pp.43-48
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    • 1997
  • To exam infestation rate and removal rate of head louse, we did delousing at 27 primary schools and 19 kindergartens established as an annex to the primary school in Namwon-shi, Jollabuk-do, Korea, from May to December 1995. Total of 3123 subjects were examined ed for the presence of head lice and nits The overall infestation rate was 9.6%, 9.5% in primary school children and 10.1% in kindergarten children. Among 299 infested children, 55 children evaluated by live nit had louse, and 79 children had dead nit. According to distractive research, Ibaek-myon and Songdong-myon revealed high infestation rate of 27.3%, and 21.7% respectively. Infestation rate of primary school was 0 to 50.9%, kindergarten was 0 to 100%. Infestation rate of female children were higher than male in all grades. When we executed one time treatment with PARA$^{(R)}$ aerosol(bioallethrin with piperonyl butoxide), treatment rate of 65.1% was examined, 82.8% was examined in three times of treatment. We concluded that 3 times of treatments interval of 14 days were more effective than one time in the case of treatment of only infested children. In order to prevent the spread of head lice, education of school hygiene and suitable delousing attempts should be executed in the present situation.

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Effects of Several Medicinal Plants Extract on Survival Rate, Chlorophyll Contents and Photosynthetic Electron Transport Activity of Liverwort Photoautotrophic Cultured Cell (약용식물 추출액이 우산이끼 자가관양배양세포의 생존율, 엽록소함량 및 광합성전자전달 활성에 미치는 영향)

  • 정형진;권순태;김시무
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.40 no.2
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    • pp.133-141
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    • 1995
  • The effects of allelochemicals from medicinal plants have been studied as photo-synthetic inhibitor for photoautotrophic(PA) cultured cells. The extracts from 9 plant species were used for measuring the physiological effects on the liverwort cultured cell in following areas; germination inhibition, chlorophyll contents, hill activity, cell viability, photosynthetic oxygen evolution,and protein pattern changes on SDS PAGE. Germination inhibitions were detected in all plant after treating with 10% extract. Especially, treatment with 10% extract from Pulsatilla koreana and Aconitum carmichael inhibited germinations completely. Chlorophyll fornation was inhibited completely by treating PA cells with extract of Pulsatilla koreana, whose effect was similar to that of DCMU 10-3M, inhibitor for photosynthetic electron trans-fer. The treatment with extract from Pulsatilla koreana on PA cell showed the highest hill activity and the lowest cell viability among extracts studied. Oxygen releasing has been decreased down to 14-77% after treating with extracts from Pinellia ternata, Araliacont inentaila, Pulsatilla koreana and Vitex rotundifolia. Especially, 60$\mu$l of Pulsatilla koreana extract into 2ml mixture of PA cell inhibit-ed oxygen release up to 50%. Protein bands on SDS-PAGE, 14kD, 31kD, 41kD, 53kD, and 73kD, were not detected after treating Pulsatilla koreana extract on PA cells.

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Development of the Better Soil Conservation Measures with Special References to Yam Hillside Farming (경사지(傾斜地) 농업기술(農業技術) 개량(改良)을 위한 효과적(效果的)인 토양보전공법(土壤保全工法) 개발(開發)에 관한 연구(硏究))

  • Woo, Bo Myeong
    • Journal of Korean Society of Forest Science
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    • v.54 no.1
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    • pp.60-67
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    • 1981
  • The run-off experiment plots had been established for eight sets of plot comprising four treatments with two replications on $20^{\circ}$ slope land having the Wait-A-Bit Clay soil(locally known), at the Olive River Soil Conservation Centre, Trelawny in Jamaica. The location of plots was about 820 metres m.s.l. and sloped north-west. Each plot size was determined as $40m^2$ having 2.7 m wide and 15.8 m long along slope. All of the run-off soil and water were collected by using the receiving tanks through the collection troughs and conveyance pipes. These run-off materials were measured and sampled, dried and computed for determination of the soil loss from each treatment of plots. During the first period of experiment for about 10 month which was one crop-year cycle of yam crop, total amount of 1,295 mm rainfall received. The heaviest daily rainfall was recorded as 116.2 mm on August 5 followed by 100.4 mm on August 6, 1980. The soil sediment had been collected and analysed for eleven times during this experiment. Total amounts of soil sediment as over-dried weight by the treatment plot were estimated as 182 ton/ha from treatment I, 105 tons/ha from treatment II, 50 tons/ha from treatment III, 43 tons/ha from treatment IV respectively. It is recommendable at present that the treatment III and IV measure which treated with contour mounds with the hillside ditch and grass buffer strip should be adopt4ed for hillside farming particularly with yam cultivation in Jamaica.

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Analysis of Research Methodologies and Contents of Papers in Journal of Engineering Education Research ('공학교육연구' 논문들에 대한 연구방법론과 내용의 분석)

  • Kim, Jin-Soo
    • Journal of Engineering Education Research
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    • v.10 no.2
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    • pp.19-43
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    • 2007
  • The Korean Society for Engineering Education (KSEE) was founded in 1994, and the Journal of Engineering Education Research has published since 1998. The purpose of the study was to analyze the research methodologies and contents for all 126 papers which were published from 1998 to 2005. A statistical package SPSS(ver. 15.0) was used to analyze the coding data of all papers. The research contents were as follows: (1) A classification of the number of papers published according to year and researcher features (gender, institution, major field, number of authors, etc) was performed, (2) The analysis of research methodologies and contents of the papers published was performed, (3) Strategies to improve the quality of the journal were suggested by discussion from the analysis results. The results showed that the development research method was used most frequently, most papers were mode by major scholars of electrical and electronic engineering and scholars of Yonsei University made the most papers. In order to use the survey research method, the sampling methods were mainly used by total number, purposive, convenience, stratified sampling method, etc, questionnaire was used of 89.5%, descriptive statistics of frequency/% was used of 50%. To conduct the experimental research method, the models of nonequivalent groups posttest-only design and one-group pretest-posttest design were adopted, respectively. Finally, research strategies and new direction for improving the engineering education journal's papers at the section of discussion and suggestion were suggested.

A research of thermoplastic elastomer PP(Poly Propylene)/SEBS(Styrene Ethylene Butylene Styrene) blends (열가소성 탄성중합체인 PP/SEBS 혼합 연구)

  • Han, Hyun Kak
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.8
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    • pp.562-570
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    • 2018
  • New physical properties of polymer materials were obtained by blending two or three different type of polymers. TPE is used widely in the display, automotive and electronics industries. Consumers have sought emotionally more sensitive and advanced interior automotive parts. A polymer with high foamibility (Ed note: Please check this.) and flowability would be more plausible. TPE composed of foam is a good polymer material to satisfy these trends. In this research, two different TPE were tested, focusing on foamibility and flowability. Two type of TPE were prepared. The first was blended Homo-PP, oil and SEBS. The second was Co-PP, oil and SEBS. The blending temperatures were $180^{\circ}C$, $190^{\circ}C$, and $260^{\circ}C$(second one). The blending speed was 50rpm and blending time was 5 min. The MI of the blended material was affected by the MI of PP and not affected by the blending temperature. The hardness and tensile elasticity were less affected by the MI of PP and blending temperature. The hardness and tensile elasticity were lower at a higher SEBS/Oil content ratio. The soft touch feel was higher with high SEBS/Oil contents. The IPN (Interpenentration polymer network) structure was observed by dissolving the SEBS/Oil layer in xylene. Strain-hardening phenomena also was observed. TPE behaves in a rubber and foamed closed-cell improved its stability.

Factors affecting patient safety behavior and performance of infection control among nursing students (간호대학생의 환자안전행위 및 감염관리 수행도에 영향을 미치는 요인)

  • Lee, Suzy;Shin, Gisoo;Cho, Mi-Kyoung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.8
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    • pp.343-352
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    • 2018
  • This study was conducted to identify the factors influencing patient safety behavior and performance of infection control in nursing students. This study was a descriptive survey based on data collected from August 28, 2017, to September 22, 2017 from 174 third and fourth year nursing students at E university located in S city of Gyeonggi. The collected data were analyzed using the PASW 23.0 program to conduct an independent t-test, one-way ANOVA, post-hoc Scheffe's test, Pearson's correlation, and multiple regression. The average scores of patient safety behavior and performance of infection control were $4.00{\pm}0.55$ and $4.31{\pm}0.50$, respectively. Patient safety behavior and performance of infection control showed a strong positive correlation. Patient safety behavior was positively influenced by confidence levels of patient safety and awareness of the infection control, and the explanatory power of the model (R2)[ED highlight - should this be R2? If so, change throughout the paper.] was 55.1%. Predictors of the performance of infection control were patient safety knowledge, confidence levels regarding patient safety, and awareness of infection control, and the R2 was 68.1%. Common factors influencing patient safety behavior and infection control performance were patient safety confidence and development of effective clinical practicum education programs to increase confidence in patient safety and infection control.

The Effect of the Characteristics of the Social Commerce's Buyer on the Customer Satisfaction and Loyalty (외식소비자의 소셜커머스 구매특성이 고객만족 및 충성도에 미치는 영향)

  • Lee, Chang Kyoung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.2
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    • pp.353-358
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    • 2020
  • The new sales method of social commerce in food service market is growing steadily. Over 50 percent of the social commerce market is food service product. Food service companies are using social commerce, which is discount sales, as a marketing tool. There are many food service companies using social commerce as a sales and marketing tool. However, little research has investigated food service customers. Thus, this study suggests how food service customer's purchasing factor affects customer's satisfaction and loyalty of the supplier and business operator. Social commerce's purchasing characteristic factors are selected based on a previous study. Purchasing factor is divided into supplier and business operator side and the impact of the relationships between its subordinate factors (price discount, offering diversity, mutual action, brand intimacy) and customer's satisfaction is analyzed. As a result, price discount and brand intimacy show higher results. Offering diversity and brand intimacy of purchasing factor on business operator side shows a higher impact on the relationship between loyalty and ?? (Ed- 'the relationship between A and B'; what is B?). The study implications are as follows. The food service industry should establish different marketing strategies to apply social commerce and compare with social commerce business operators, because the actual place where customers use food service is food service restaurants and not just social commerce websites.

The Ethanol Extract of Red Ginseng Enhances Anti-Tumor Effects Using Co60 Gamma Irradiation (홍삼의 에탄올 추출물의 감마선 조사를 통한 항암효과 증대)

  • Hur, Jung-Mu;Kim, Dong-Ho
    • Journal of Applied Biological Chemistry
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    • v.54 no.1
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    • pp.15-20
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    • 2011
  • Red ginseng is one of the most popular traditional medicines in Korea. In this study, we developed a new technique in which ethanol extract of $\underline{r}$ed $\underline{g}$inseng (HRG) was exposed to the $Co^{60}$ gamma radiation ranging from 1~5 kGy. The irradiated HRG (IHRG) were analyzed by high performance liquid chromatography (HPLC) to determine any compositional changes of ginsenosides due to irradiation. No appreciable difference was observed in the HPLC pattern of ginsenosides of HRG. Using MTT assay, the cytotoxicity effect was significantly increased by IHRG compared to HRG. The $LD_{50}$ concentration was $30{\mu}g/mL$ for IHRG-1 (1 kGy), and $15{\mu}g/mL$ for IHRG-5 (5 kGy). The evidences of apoptosis, such as nuclei cleavage and Annexin V staining, were observed in the human prostate cancer PC-3 cells treated with the IHRG. Additionally, the level of reactive oxygen species (ROS) was apparently elevated by IHRG. We also studied the inhibitory effect of IHRG on the growth rate of tumor xenografts in BALB/c male mice. The tumor growth rates were inhibited by 56.9 and 76.1% in mice treated with 10 mg/kg of IHRG-1 and IHRG-5, respectively, compared with control group (21.1%). These results suggest that some biologically active and soluble components in HRG can be more effectively enhancement of anti-tumor effects using irradiation.