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Development of Educational Science Magic Program in Elementary Science Education and Effects of its Application (초등과학 수업에서 과학교육마술 프로그램의 개발 및 적용에 따른 효과)

  • Yoon, Jung-Hyun;Choi, Sun-Young
    • Journal of Science Education
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    • v.37 no.1
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    • pp.52-67
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    • 2013
  • The purpose of this study was to examine the effect of educational science magic program on creative problem solving ability, inquiry skill, and scientific attitude in elementary school science. For this, two classes of 3th grade were chosen in the J elementary school located in Suwon city as the experimental class(30 students) and the comparative class(30 students). The two groups were selected through a diagnostic examining program. Instruction using educational science magic program was applied to the experimental class. The results of this study were as follows. 1. the creative problem solving ability of the experimental class has statistically meaningful differences and improved, compared with the comparative class(p<.05). 2. the scientific inquiry skill was improved, but it has no meaningful difference statistically. However, science tasks applied educational science magic program had valuable significance to ability of measure(p<.05). 3. the scientific attitude score also was improved, but it has no meaningful difference statistically. However, science tasks applied educational science magic program had valuable significance to endurance(p<.05). 4. the results of survey showed that educational science magic program influence students' interests and concerns in science, class participation, pleasure in class, and comprehension of what is said in class positively. Therefore, a educational science magic program applied in this study might be useful to improve the creative problem solving ability, interests and concerns in science, class participation, pleasure in class, and comprehension of what is said in class.

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Aoric Valve Lesion in Type I Ventricular Septal Defect (제1형 심실중격결손에서 대동맥판막 병변)

  • 김관창;임홍국;김웅한;김용진;노준량;배은정;노정일;윤용수;안규리
    • Journal of Chest Surgery
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    • v.37 no.6
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    • pp.492-498
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    • 2004
  • Background: In this study, we investigated the risk factors for the development or progression of aortic regurgitation(AR) in patients with type I ventricular septal defect (VSD) to determine the optimal surgical timing and strategy. Material and Method: Three-hundred and ten patients with type I VSD with or without AR were included. The mean of age was 73.7$\pm$114.7 (1-737) months. One hundred and eighty six patients (60%) had no AR, 83 (27%) had mild AR, 25 (8%) had moderate AR and 16 (5%) had severe AR. Aortic valve was repaired in 5 patients and replaced in 11 patients with closure of VSD in the first operation. Four patients required redo aortic valve repair and 11 patients required redo aortic valve replacement. Age at operation, association with aortic valve prolapse, Qp/Qs, systolic pulmonary arterial pressure, VSD size and systolic pulmonary artery to aortic pressure ratio(s[PAP/AP]) were included as risk factors analysis for the development of AR. The long-term result of aortic valve repair and aortic valve replacement were compared. Result: Older age at operation, association with aortic valve prolapse, high Qp/Qs, and s[PAP/AP] were identified as risk factors for the development of AR (p<0.05, Table 2). The older the patient at the time of operation, the higher the severity of preoperative AR and the incidence of postoperative AR (p<0.05, Table 1, Fig. 1). For the older patients at operation, aortic valve repair had higher occurrence of AR compared to those who had aortic valve replacement (p<0.05, Fig. 2). Conclusion: From the result of this study, we can concluded that early primary repair is recommended to decrease the progression of AR. Aortic valve repair is not always a satisfactory option to correct the aortic valve pathology, which may suggest that aortic valve replacement should be considered when indicated.

Diversity and Geographical Relationships by SSR Marker in Subgenus Soja Originated from Korea (SSR 마커에 의한 한국 원산 Soja 아속의 다양성과 지리적 유연관계)

  • Cho Yang-Hee;Yoon Mun-Sup;Lee Jeong-Ran;Baek Hyung-Jin;Kim Chang-Yung;Kim Tae-San;Cho Eun-Gi;Lee Hee-Bong
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.51 no.3
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    • pp.239-247
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    • 2006
  • This study was carried out to investigate polymorphism, gene diversity, and geographical relationships of 81 Korean wild (Glycine soja) and 130 cultivated soybeans (G. max) using seven simple sequence repeat (SSR) markers. A total of 144 alleles were observed in 211 accessions with an average of 20.6. Each SSR loci showed 13 (Satt532) to 41 (Sat_074) multialleles. The range of alleles within the loci was wider in wild soybean than the cultivated soybeans. The average genetic diversity values were 0.88 and 0.69 in wild and cultivated soybeans, respectively. In a scatter diagram of wild and cultivated soybeans based on canonical discriminant analysis, CAN1 accounted for 84.2% while CAN2 did 8.5%. Two species were grouped into three: group I (G. max), group II (G. soja), and group III (complex of G. max and G. soja). The geographical relationships of wild soybean were distinguished into two groups: Gyeonggi for Group I, and Gyeongsang, Jeolla, Gangwon, and Chungcheong for Group II. Those of cultivated soybeans were distinguished into Gyeonggi, Gangwon, and Gyeongsang for Group I, and Jeolla and Chungcheong for Group II. Therefore, the geographical relationships of wild soybeans were well typified based on the ecosystems of the Korean peninsula.

Ethical Fashion Consumer Behavior in Korea - Factors Influencing Ethical Fashion Consumption - (한국에서의 윤리적 패션 소비자 행동 - 윤리적 패션 소비에 영향 미치는 요인을 중심으로 -)

  • Koh, Ae-Ran;Noh, Ji-Yeon
    • Journal of the Korean Society of Clothing and Textiles
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    • v.33 no.12
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    • pp.1956-1964
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    • 2009
  • Understanding ethical fashion consumers in Korea is essential for the expansion of the ethical fashion market. This study analyzed ethical consumers in Korea in an examination of the factors that influence ethical purchase behavior and attitudes. The differences between ethical fashion consumers and non-ethical fashion consumers were investigated using eight variables (perceived consumer effectiveness (PCE), self-direction, benevolence, universalism, social responsibility, perceived behavioral control, face saving, and group conformity). Data were collected by means of a questionnaire through both on-line and off-line surveys from April 20 to June 7, 2009. Only the respondents knowledgeable of ethical products or ethical consumption were asked to complete the questionnaire. A total of 494 samples were used for analyses. Using independent samples t-test, the differences in each variable between two groups were examined. There were significant differences between ethical fashion consumers and non-ethical fashion consumers in attitudes toward ethical consumption behavior, behavioral intention, PCE, self-direction, universalism, social responsibility, and face saving variables. The factors influencing attitude and behavior intention were investigated by step-wise regression analyses. For ethical fashion consumers, the attitudes to ethical consumption behavior were largely influenced by PCE and benevolence. Social responsibility was the most predictable variable in guiding behavioral intention. Behavioral intention was also influenced by benevolence and attitude. Group conformity was found to be negatively correlated with behavioral intention. The findings of this study provide significant guidance for marketers of ethical fashion products. This study is the start of ethical fashion consumer research in Korea and can develop into variable subfields in the future.

Histological Changes in Rat Testis by Injection of Hypertonic Saline (고장성 식염수 주사에 의한 흰쥐 정소의 해부학적 변화)

  • Kwak, Byung-Kuk;Lee, Chul-Sang;Lee, Sung-Ho
    • Development and Reproduction
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    • v.14 no.4
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    • pp.281-286
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    • 2010
  • Recent evidence has revealed that the intratesticular injection of hypertonic saline(20%) resulted in a chemically castrated state such as nadir testosterone levels in rats. To confirm the efficacy of this simple saline-injection method further, we investigated the changes in the gross and microscopic anatomy of testis. Our study comprised three groups; intact(control) group, orchidectomy group and saline-injection (experimental) group. Single dose of hypertonic saline (sterilized, $750{\mu}{\ell}/testis$) were directly administered into both testis of adult rats (about 300 g BW). Bilateral orchidectomy was performed at the same day of saline injection. Following 30 days post-injection, reproductive tissues were surgically removed, weighed and fixed for histological examination. The body weights were not changed in both orchidectomy group and saline-injection group when compared to those in intact group. The wet weights of testis were significantly decreased in saline-injection group when compared to those in intact group. The wet weights of epididymis and seminal vesicle and prostate were significantly decreased in orchidectomy group and saline-injection group when compared to those in intact group. Macroscopically, the testes exerted slight atrophy and the tunica albuginea seemed to be intact in saline injection group. Histologically, however, larger parts of testicular tissue underwent necrosis and were barely recognizable after hematoxylin-eosin staining. In the same section, only the opposite part of the injection site was stained showing abnormal state of cell layers mostly fibrosis and infiltrated leukocytes. Sloughing of immature germ cells from the basement membrane along with shedding cells in the intraluminal space was notable in most seminiferous tubules from the saline injected testis. The present study confirmed that the direct injection of hypertonic saline into testis can induce a castration-like, testosterone-depriving effects on accessory sex organs. Our findings suggest that the efficacy of this less expensive and minimally invasive method seems to be almost even with that of conventional orchidectomy and chemical castration, though more in-depth evaluation should be supported.

Skarn Formation in Metamorphic Rocks of the Chungju Mine Area (충주광산 지역 계명산층의 텅스텐 스카른화작용)

  • Kim, Gun-Soo;Park, Maeng-Eon
    • Economic and Environmental Geology
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    • v.28 no.3
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    • pp.185-197
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    • 1995
  • Tungsten skarns in the Chungju mine which consists mainly of strata-bound type iron ore deposits are found in the vicinity of the contact between the age-unknown Kyemeongsan Formation and granitic rock intrusions of Mesozoic age($134{\pm}2Ma$). Tungsten skarns were formed extensively from alumina and silica-rich schistose rocks by the introduction of calcium and iron from hydrothermal solution. The skarns comprise a metasomatic column and are subdivided into four facies; garnet facies, wollastonite facies, epidote facies and chlorite facies. The skarn process in time-evolutional trend can be divided broadly into the four facies in terms of the paragenetic sequence of calc-silicates and their chemical composition. Skarn and ore minerals were formed in the following sequence; (1) garnet facies, adjacent to biotite granite, containing mainly garnet(>Ad96) and magnetite, (2) wollastonite facies containing mainly wollastonite and garnet(Ad95~60), (3) epidote facies, containing mainly epidote(Ps35~31), quartz, andradite-grossular(Ad63~50), and scheelite, (4) chlorite facies, adjacent to and replacing schist, containing mainly chrolite, muscovite, quartz, calcite, epidote(Ps31~25), hematite and sulfides. The mineral assemblage and mineral compositions. suggest that the chemical potentials of Ca and Fe increased toward the granitic rock, and the component Al, Mg, K, and Si decreased from the host rock to granitic rock. The homogenization temperature and salinity of fluid inclusion in scheelite, quartz and epidote of epidote facies skarn is $300-400^{\circ}C$ and 3-8wt.% eqiv. NaCl, respectively. ${\delta}^{34}S$ values of pyrite and galena associated with chlorite facies skarn is $9.13{\sim}9.51%_{\circ}$ and $5.85{\sim}5.96%_{\circ}$, respectively. The temperature obtained from isotopic com· position of coexisting pyrite-galena is $283{\pm}20^{\circ}C$. Mineral assemblages and fluid inclusion data indicate that skarn formed at low $X_{CO_2}$, approximately 0.01. Temperature of the skarn mineralization are estimated to be in the range of $400^{\circ}C$ to $260^{\circ}C$ and pressure to be 0.5 kbar. The oxygen fugacity($fo_2$) of the skarn mineralization decreased with time. The early skarn facies would have formed at log $fo_2$ values of about -25 to -27, and late skarn facies would have formed at log $fo_2$ values of -28 to -30. The estimated physicochemical condition during skarn formation suggests that the principal causes of scheelite mineralization are reduction of the ore·forming fluid and a decrease in temperature.

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A Study on Detailed Bathymetry and Geophysical Characteristics of the Summit of the Dokdo Volcano (독도 화산체 정상부해역의 정밀해저지형 및 지구물리학적 특성 연구)

  • Kim, Chang Hwan;Park, Chan Hong;Lee, Myoung Hoon;Choi, Soon Young;Jou, Hyeong Tae
    • Economic and Environmental Geology
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    • v.45 no.6
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    • pp.685-695
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    • 2012
  • We studied the detailed bathymetry and the geophysical characteristics of the summit of the Dokdo volcano using mutibeam echosounding and geophysical survey data. The bathymetry around the main east and west islets of the Dokdo volcano shows very shallow within about 10 m water depth. From near islets to about 30 m b.s.l., the shallow water area has very steep slope and many irregular sunken rocks. The area from about 30 m to about 80 m b.s.l. shows gentle rises and falls, and less steep slope. The area from 80 m b.s.l. has gradually flat undulation and smooth slope seabaed and is extended to offshore. The main islets of the Dokdo volcano and the rocky sea bottom elongated from the islets might be the residual part of the eroded and collapsed main crater of the Dokdo volcano. The bathymetry and the seafloor image(from backscattering) data show small craters, assumed to be formed by the eruption of later volcanism. The seafloor images propose that, except some areas with shallow sand sedimentary deposits, there are typical rocky bottom such as rocky protrusions and lack of sediments in the main morphology of the survey area. The stepped slopes of the seabed are deduced to be submarine terraces. The several prominent submarine terraces are found at the summit of the Dokdo volcano, suggesting repetition of sea level changes(transgressions and regressions) in the Quaternary. The results of the magnetic anomaly and the analytic signal have a good coherence with other geophysical consequences regarding to the location of the residual crater.

Characteristics of Groundwater Contamination Caused by Seawater Intrusion and Agricultural Activity in Sacheon and Hadong Areas, Republic of Korea (해수침투와 농업활동에 의한 사천-하동 해안지역 지하수의 오염 특성)

  • Kim, Hyun-Ji;Hamm, Se-Yeong;Kim, Nam-Hoon;Cheong, Jae-Yeol;Lee, Jeong-Hwan;Jang, Sung
    • Economic and Environmental Geology
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    • v.42 no.6
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    • pp.575-589
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    • 2009
  • Groundwater has been extracted for irrigation in Sacheon-Hadong area, which is close to the South Sea. We analyzed chemical components of groundwater to examine the effects of seawater intrusion and agricultural activities in the study area. Most groundwater samples displayed the Na/Cl concentration ratios similar to that of seawater (0.55) with an increasing tendency of electrical conductivity ($227-7,910\;{\mu}S/cm$) towards the coast. In addition, statistical interpretation of the cumulative frequency curves of Cl and $HCO_3$ showed that 30.1% of the groundwater samples were highly affected by seawater intrusion. Groundwaters in the study area mostly belonged to the Ca-Cl and Na-Cl type, demonstrating that they were highly influenced by seawater intrusion and cation exchange. The result of oxygen-hydrogen isotope analysis demonstrated slightly higher $\delta^{18}O$ ((-8.53)-(-6.13)‰) and ${\delta}D$ ((-58.7)-(-43.7)‰) comparing to mean oxygen-hydrogen isotope ratios in Korea. As a result of nitrogen isotope analysis, the $\delta^{15}N-NO_3$ values ((-0.5)-(19.1)‰) indicate two major sources of nitrate pollution (organic nitrogen in soil and animal and human wastes) and mixed source of the two. However, denitrification may partly contribute as a source of nitrogen. According to factor analysis, four factors were identified among which factor 1 with an eigenvalue of 6.21 reflected the influence of seawater intrusion. Cluster analysis indicated the classification of groundwater into fresh, saline, and mixed ones.

Comparative Assessment of Specific Genes of Bacteria and Enzyme over Water Quality Parameters by Quantitative PCR in Uncontrolled Landfill (정량 PCR을 이용한 비위생 매립지의 특정 세균 및 효소 유전자와 수질인자와의 상관관계 평가)

  • Han, Ji-Sun;Sung, Eun-Hae;Park, Hun-Ju;Kim, Chang-Gyun
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.8
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    • pp.895-903
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    • 2007
  • As for the increasing demanding on the development of direct-ecological landfill monitoring methods, it is needed for critically defining the condition of landfills and their influence on the environment, quantifying the amount of enzymes and bacteria mainly concerned with biochemical reaction in the landfills. This study was thus conducted to understand the fates of contaminants in association with groundwater quality parameters. For the study, groundwater was seasonally sampled from four closed unsanitary landfills(i.e. Cheonan(C), Wonju(W), Nonsan(N), Pyeongtaek(P) sites) in which microbial diversity was simultaneously obtained by 16S rDNA methods. Subsequently, a number of primer sets were prepared for quantifying the specific gene of representative bacteria and the gene of encoding enzymes dominantly found in the landfills. The relationship between water quality parameters and gene quantification were compared based on correlation factors. Correlation between DSR(Sulfate reduction bacteria) gene and BOD(Biochemical Oxygen Demand) was greater than 0.8 while NSR(Nitrification bacteria-Nitrospira sp.) gene and nitrate were related more than 0.9. A stabilization indicator(BOD/COD) and MTOT(Methane Oxidation bacteria), MCR(Methyl coenzyme M reductase), Dde(Dechloromonas denitrificans) genes were correlated over 0.8, but ferric iron and Fli(Ferribacterium limineticm) gene were at the lowest of 0.7. For MTOT, it was at the highest related at 100% over BOD/COD. In addition, anaerobic genes(i.e., nirS-Nitrite reductase, MCR. Dde, DSR) and DO were also related more than 0.8, which showing anaerobic reactions generally dependant upon DO. As demonstrated in the study, molecular biological investigation and water quality parameters are highly co-linked, so that quantitative real-time PCR could be cooperatively used for assessing landfill stabilization in association with the conventional monitoring parameters.

Effect of Fly Ash Fertilizer on Paddy Soil Quality and Rice Growth (비산재로 제조한 비료가 논토양 질과 벼 생육에 미치는 영향)

  • Oh, Se Jin;Yun, Hyun Soo;Oh, Seung Min;Kim, Sung Chul;Kim, Rog Young;Seo, Yung Ho;Lee, Kee Suk;Ok, Yong Sik;Yang, Jae E.
    • Journal of Applied Biological Chemistry
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    • v.56 no.4
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    • pp.229-234
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    • 2013
  • Coal ash can be added to agricultural soils to increase the chemical properties of soil such as pH, cation exchange capacity and nutrient availability of - B, Ca, Mo etc-. Therefore, the main purpose of this study was to evaluate the feasibility of fly ash as a soil amendment in paddy soils. Selected fly ash was mixed with bentonite and calcium hydroxide at the ratio of 80:15:5 (w/w) and manufactured as a pellet type at the size of 10 mm. Field experiments were conducted to evaluate the effects of fly ash fertilizer on the soil quality and crop growth compare to the control (no fertilizer) and, - traditional fertilizer. Results showed that soil pH and organic matter in paddy soils after applying the manufactured fly ash fertilizer were not increased compared to the other two treatments. However, the concentration of available phosphate and silicate in paddy soils were higher than those of the control and traditional fertilization. With regard to crop growth, no significant difference was observed between three different treatments. However, the content of protein in the rice grain cultivated with the fly ash fertilizer was higher than in the rice cultivated by other two treatments. Overall, fly ash fertilizer could increase the concentration of available silicate and phosphate in the paddy soil and improve the rice quality. In conclusion, fly ash can be utilized in agricultural soils as soil amendment, especially in the rice paddy soil.