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COMPARISON OF COMPRESSIVE STRENGTH AND SURFACE MICROHARDNESS BETWEEN FLOWABLE COMPOSITE RESIN AND GIOMER (유동성 자이오머와 복합 레진의 압축 강도 및 표면 미세 경도 비교)

  • Kim, Jong-Soo
    • Journal of the korean academy of Pediatric Dentistry
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    • v.39 no.4
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    • pp.383-388
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    • 2012
  • The aim of this study was to compare the compressive strength and the surface microhardness of Beautifil flow (Shofu, Kyoto, Japan) with $Filtek^{TM}$ Z350, Z350XT (3M ESPE, USA). Fifteen specimens from each material were fabricated for testing. Compressive strength was measured by using a universal testing machine at a crosshead speed of 1 mm/min. Surface microhardness values were measured by using Vickers hardness tester under 4.9 N load and 10 seconds dwelling time. The compressive strength of Group 2 $Filtek^{TM}$ Z350XT shows the highest value as $218.7{\pm}18.4$ MPa and Group 1 $Filtek^{TM}$ Z350 was $205.5{\pm}27.1$ MPa. Group 3 Beautifil flow F00 was $176.5{\pm}30.3$ MPa, and Group 4 Beautifil flow F10 was $173.4{\pm}26.2$ MPa. The compressive strength of Group 2 is higher than Group 3 and 4 (p < 0.05). The surface microhardness of Group 2 $Filtek^{TM}$ Z350XT shows the highest value as $39.1{\pm}2.1$ and Group 4 Beautifil flow F10 was $27.9{\pm}1.8$. And Group 3 Beautifil flow F00 was $23.1{\pm}1.1$, Group 1 $Filtek^{TM}$ Z350 was $20.4{\pm}0.9$. There was a statistical significant difference in surface microhardness between all groups (p < 0.05). In conclusion, the compressive strength of giomer was below the level of flowable composite resin. However, the surface microhardness of giomer is comparable to that of flowable composite resin. Giomer would be the good alternative to composite resin, if there is improvement of the compressive strength of giomer.

Seasonal Variations in Mood and Behavior in Korean High School Students (한국의 고등학생에서 기분과 행동의 계절적 변동)

  • Lee, Moon-Soo;Joung, Yoo-Sook;Hong, Sung-do-David;Ko, Young-Hoon;Kim, Seung-Hyun;Joe, Sook-Haeng;Jung, In-Kwa;Kim, Leen;Lee, Heon-Jeong
    • Sleep Medicine and Psychophysiology
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    • v.12 no.2
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    • pp.111-116
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    • 2005
  • Objectives: Although many reports have been written on seasonal variations in mood and behavior in foreign countries, few reports have dealt with Korean adolescents, except medical students. The goal of this study was to estimate the frequency of seasonal variations in mood and behavior among Korean high school students. Methods: A total of 656 high school students living in southeastern Seoul participated in this study. The subjects were investigated with the Korean translated version of the Seasonal Pattern Assessment Questionnaire (SPAQ), and their responses were evaluated for seasonal patterns in mood and behavior change according to Kasper's criteria to make SAD (seasonal affective disorder) or SSAD (subclinical seasonal affective disorder) diagnosis. Results: A total of 565 subjects completed the questionnaire and the responses (M:F=324:241) were collected and used for analysis. The mean age was 16.73 (SD=0.65) years, and mean global seasonality score 5.88 (SD=4.72). Of the respondents, 413 (73.1%) reported problems related with seasonal changes. Total prevalence rates were 13.6% for SAD, 10.8% for S-SAD. The estimated frequencies were 5.1% for summer SAD, 3.2% for summer S-SAD, 0.5% for winter SAD and 1.1% for winter S-SAD. The prevalence rate of summer SAD or S-SAD was higher than winter SAD or S-SAD. Conclusion: The subjects showed a higher prevalence rate of summer type than winter type in SAD or S-SAD. These results were similar to those of other studies carried out in East Asian countries. However, the unpleasant feelings resulting from high temperature and humidity in summer rather than depression may have influenced the results. Therefore, it is necessary to make new SAD criteria of the SPAQ suitable for East Asian countries.

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Proteomic Assessment of the Relevant Factors Affecting Pork Meat Quality Associated with Longissimus dorsi Muscles in Duroc Pigs

  • Cho, Jin Hyoung;Lee, Ra Ham;Jeon, Young-Joo;Park, Seon-Min;Shin, Jae-Cheon;Kim, Seok-Ho;Jeong, Jin Young;Kang, Hyun-sung;Choi, Nag-Jin;Seo, Kang Seok;Cho, Young Sik;Kim, MinSeok S.;Ko, Sungho;Seo, Jae-Min;Lee, Seung-Youp;Shim, Jung-Hyun;Chae, Jung-Il
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.11
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    • pp.1653-1663
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    • 2016
  • Meat quality is a complex trait influenced by many factors, including genetics, nutrition, feeding environment, animal handling, and their interactions. To elucidate relevant factors affecting pork quality associated with oxidative stress and muscle development, we analyzed protein expression in high quality longissimus dorsi muscles (HQLD) and low quality longissimus dorsi muscles (LQLD) from Duroc pigs by liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based proteomic analysis. Between HQLD (n = 20) and LQLD (n = 20) Duroc pigs, 24 differentially expressed proteins were identified by LC-MS/MS. A total of 10 and 14 proteins were highly expressed in HQLD and LQLD, respectively. The 24 proteins have putative functions in the following seven categories: catalytic activity (31%), ATPase activity (19%), oxidoreductase activity (13%), cytoskeletal protein binding (13%), actin binding (12%), calcium ion binding (6%), and structural constituent of muscle (6%). Silver-stained image analysis revealed significant differential expression of lactate dehydrogenase A (LDHA) between HQLD and LQLD Duroc pigs. LDHA was subjected to in vitro study of myogenesis under oxidative stress conditions and LDH activity assay to verification its role in oxidative stress. No significant difference of mRNA expression level of LDHA was found between normal and oxidative stress condition. However, LDH activity was significantly higher under oxidative stress condition than at normal condition using in vitro model of myogenesis. The highly expressed LDHA was positively correlated with LQLD. Moreover, LDHA activity increased by oxidative stress was reduced by antioxidant resveratrol. This paper emphasizes the importance of differential expression patterns of proteins and their interaction for the development of meat quality traits. Our proteome data provides valuable information on important factors which might aid in the regulation of muscle development and the improvement of meat quality in longissimus dorsi muscles of Duroc pigs under oxidative stress conditions.

Nutritional Assessment and the Effectiveness of Dietary Counseling in Infants and Young Children with Iron Deficiency Anemia (철결핍성 빈혈을 가진 영유아에서 영양학적 평가 및 영양상담 효과)

  • Kim, Ja Kyoung;Ko, Eun Young;Lee, Yu Jin;Jun, Yong Hun;Kim, Soon Ki
    • Clinical and Experimental Pediatrics
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    • v.46 no.1
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    • pp.11-16
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    • 2003
  • Purpose : Iron deficiency is still the most common nutrient deficient disorder despite the improvement in general health and nutrition. This study is designed to evaluate the dietary history of infants and young children with iron deficiency anemia(IDA) and the effects of nutritional counseling. Methods : This study was conducted on 120 children from 6 to 36 months of age with IDA. Their parents completed a questionnaire and took counsel for nutrition. IDA was defined as Hb <11.0 g/dL, ferritin <10 ng.mL or transferrin saturation <15%, or Hb increase >1 g/dL after iron preparation. The questionnaire consisted of their feeding patterns, weaning time and kinds of food. Results : In the 120 infants and young children aged from 6 to 36 months, the parents of 82 cases was counseled about nutrition. Fifty six infants among 82 cases have started weaning and the main foods of weaning were rice and/or rice gruel. Nutritional problems in weaning were that some children over one year of age were using a bottle, and parents restricted weaning food at will because of allergic disease or chronic disease. Most parents were satisfied with the nutritional counseling given from a clinical dietitian and showed good compliance. Conclusion : Many infants and young children with IDA were provided with non iron-fortified foods and made an inadequate wean. Most parents were satisfied with the nutritional counseling and showed good compliance. The need of dietary counseling was required for prevention and treatment of iron deficiency anemia because of inadequate weaning.

DEVELOPMENT OF THREE DIMENSIONAL MEASURING PROGRAM WITH FRONTAL AND LATERAL CEPHALOMETRIC RADIOGRAPHS -PART 1. COMPUTATION OF THE THREE-DIMENSIONAL COORDINATES BY COMPENSATION OF THE ERROR OF THE HEAD POSITION IN ORDINARY NON-BIPLANAR CEPHALOSTAT- (정모 및 측모 두부 방사선 규격사진을 이용한 3차원 계측 프로그램의 개발 -1. 단일 방사선원으로 촬영된 두부 방사선사진의 두부 위치 보정을 이용한 3차원 좌표의 산출-)

  • Lee, Geun-Ho;Lee, Sang-Han;Jang, Hyon-Joong;Kwon, Tae-Geon
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.27 no.3
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    • pp.214-220
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    • 2001
  • The clinical application of the three-dimensional radiographic technique had been limited to standard Broadbent-Bolton cephalometer with biplanar stereoradiography. We developed a new method for compensating the error of head position in ordinary non-biplanar cephalostat. It became to possible to use the three dimensional cephalogram commonly in clinical bases. 1. The method of methemetical compensation of head positioning error in non-biplanar condition was evaluated with dry skull. The error of the method of first and the second trial was $0.46{\pm}1.21$, $0.33{\pm}0.90mm$, which means the error of the head positioning correction in conventional cephalogram was within clinical acceptance. 2. The reproducibility of this system for clinical application was 0.54 mm ($-2.99{\sim}2.26mm$) which defines the absolute mean difference of the first and second trial. Compare to the The landmark identification error $1.2{\pm}1.6mm$, the error of the measurement was within the range of landmark identification error. The result indicates the adequate clinical accuracy of the computation of three-dimensional coordinates by compensation of the error of the head position in ordinary non-biplanar cephalostat.

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An Initiative Study on Relationship between Algal Blooms and Asian Dust for Regulation of Algal Blooms (조류 성장 억제를 위한 녹조 및 적조 발생과 황사의 상관관계 초기적 연구)

  • Kim, Tai-Jin;Jeong, Jaechil;Seo, Rabeol;Kim, Hyung Moh;Kim, Dae Geun;Chun, Youngsin;Park, Soon-Ung;Yi, Sehyoon;Park, Jun Jo;Lee, Jin Ha;Lee, Jay J.;Lee, Eun Ju
    • KSBB Journal
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    • v.29 no.4
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    • pp.285-296
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    • 2014
  • Although the problems of the algal blooms have been world-widely observed in freshwater, estuary, and marine throughout the year, it is not yet certain what are the basic causes of such blooms. Consequently, it is very difficult to predict when and where algal blooms occur. The constituents of the Asian dust are in a good agreement with the elements required for the algal growth, which suggests some possible relationship between the algal blooms and the Asian dust. There have been frequently algal blooms in drinking water from rivers or lakes. However, there is no any algal blooms in upwelling waters where the Asian dust cannot penetrate into the soil due to its relatively weak settling velocity (size of particles, $4.5{\pm}1.5{\mu}m$), which implies the possible close relationship of the Asian dust with algal blooms. The present initiative study is thus intended firstly in Korea to illustrate such a relationship by reviewing typical previous studies along with 12 years of weekly iron profiles (2001~2012) and two slant culture experiments with the dissolved Asian dust. The result showed bacterial suspected colonies in the slant culture experiment that are qualitatively in a good agreement with the recent Japanese studies. Since the diatoms require cheap energy (8%) compared to other phytoplankton (100%) to synthesize their cell walls by silicate, the present results can be used to predict algal blooms by diatoms if the concentrations of iron and silicate are available during spring and fall. It can be postulated that the algal blooms occur only if the environmental factors such as light, nutrients, calm water surface layer, temperature, and pH are simultaneously satisfied with the requirements of the micronutrients of mineral ions supplied by the Asian dust as enzymatic cofactors for the rapid bio-synthesis of the macromolecules during algal blooms. Simple eco-friendly methods to regulate the algal blooms are suggested for the initial stage of blooming with limited area: 1) to cover up the water surface with black curtain and inhibit photosynthesis during the day time, 2) to blow air (20.9%) or pure oxygen into the bottom of the water and inhibit rubisco for carbon uptake and nitrate reductase for nitrogen uptake activities in algal growth during the night, 3) to eliminate the resting spores or cysts by suction of bottom sediments as deep as 5 cm to prevent the next year germinations.

The optimal conditions to improve retrovirus-mediated transduction efficiency to NIH 3T3 cells (레트로바이러스(retrovirus)의 NIH 3T3 세포로의 유전자 전달효율을 증가시키기 위한 적절한 조건들)

  • Lee, Jun Ah;Lee, Kang-Min;Lee, Hyun Jae;Lee, Yun Jeong;Kim, Dong Ho;Lim, Jung Sub;Park, Kyung-Duk
    • Clinical and Experimental Pediatrics
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    • v.50 no.10
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    • pp.1011-1017
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    • 2007
  • Purpose : We tried to assess the optimal conditions to improve low transduction efficiency and their effect on target cells. Methods : Cultured NIH 3T3 cells were incubated with retroviral vectors bearing an enhanced green fluorescent protein (eGFP) gene. We varied the ratio of viral vectors to target cells (1:1-1:8) and the number of transfections (${\times}1$, ${\times}2$), and compared transduction efficiencies. Also, the effects of polybrene on transduction efficiency and viability of target cells were assessed. Transduction of the eGFP gene was evaluated by observing NIH 3T3 cells under a fluorescence microscope and efficiencies were measured by the percentage of eGFP positive cells using FACscan. Results : As the ratio of retroviral vectors to target cells increased, transduction efficiency was greatly improved, from 7% (1:1) to 38% (1:4). However, transduction efficiency did not increase any more when the ratio increased from 1:4 to 1:8. Cells transfected twice showed higher transduction efficiencies than cells transfected once, at a ratio of 1:8. The eGFP gene transduced to NIH 3T3 cells sustained its expression during repeated passages. However, after the third passage (day 9), the percentage of eGFP positive cells began to decline. The degree of this decline in eGFP expression was lower in cells transfected twice than in cells transfected once (P<0.05). The addition of polybrene did not have any toxic effect on NIH 3T3 cells and greatly increased transduction efficiency (P=0.007). In addition to vector component, transduction efficiency was very sensitive to culture confluence. Cells cultured and transfected in 24-well plate showed higher transduction efficiency, although cells cultured in 6- well plate proliferated more (P=0.024). Conclusion : Our data could be used as a basis for retrovirus-based gene therapy. Further study will follow using human cells as target cells.

Yield Reductions in the $F_2$ and $F_3$ Generations of Highly Promising Varietal Crosses of Corn (유망시되는 옥수수 품종간교잡의 $F_2$$F_3$에 있어서의 수량감소)

  • Chea-Yu Cho;R.M. Lantican
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.14
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    • pp.123-131
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    • 1973
  • 1. In order to evaluate the performance of the $F_2$ and $F_3$ generations of $F_1$ varietal crosses which in past trials yielded better than or as high as the recommended double-cross hybrids, eleven yellow and five white-endosperm $F_1$ varietal crosses, their $F_2$ and $F_3$ generations, and the parental open-pollinated varieties together with the standard double-cross hybrids were tested in performance trials in the 1963 wet and 1963-64 dry seasons. The former trials, however, failed due to a strong typhoon that damaged the crop. 2. Net hybrid vigor was highly manifested in grain yield in the $F_1$ varietal crosses, which on the average was 39.9 per cent of the mid-parent yields. Reduction in heterosis was 27.2 per cent in the $F_2$and 30.3 per cent in the $F_3$ generation, respectively. 3. A fairly high degree of reduction in yield occurred in the $F_2$ and $F_3$ generation. On the average, the $F_2$ generation decreased by 17.6 per cent and the $F_3$ by 20.7 per cent. The losses in two generations were exhibited in two levels; four crosses decreased by 10.9 per cent and twelve combinations by 22.0 per cent. The advanced generations of one yellow cross, Cuban Yellow Flint ${\times}$ Hawaiian Flinty Dent, and three white flint crosses, Bicol White Flint ${\times}$ Eto Blanco, College White Flint ${\times}$ Eto Blanco and Bicol White Flint ${\times}$ Nariono 330b, yielded as high as Philippine Hybrid No.1 and Philippine Hybrid No.4, respectively. 4. No significant differences in yield were obtained between the $F_2$ and $F_3$ populations, showing that genetic equilibrium was reached in $F_2$, as may be expected in view of the Hardy-Weinberg law on panmixis. 5. As in past trials, Hawaiian Flinty Dent, a variety, yielded as high as Philippine Hybrid No. 1.

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Effects of the Drainage Methods on Antioxidant Compounds and Antioxidant Activity of Ethanolic Extracts on Adzuki Bean (논 재배 배수방법이 팥 에탄올 추출물의 항산화성분 및 항산화활성에 미치는 영향)

  • Woo, Koan Sik;Jung, Ki Yuol;Song, Seuk Bo;Ko, Jee Yeon;Lee, Jae Saeng;Choi, Young Dae;Yun, Eul Soo;Jung, Tae Wook;Oh, In Seok
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.59 no.3
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    • pp.350-358
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    • 2014
  • This study investigated the changes of antioxidant compounds and antioxidant activity of adzuki bean by drainage methods in poorly drained sloping paddy field. The soil moisture contents of under pipe and open ditch drainage on very poorly drained paddy soil were $18.52{\pm}4.58$ and $19.01{\pm}4.25%$, and imperfectly drained paddy soil were $14.87{\pm}4.82$ and $18.64{\pm}3.85%$, respectively. Moisture, protein, fat and ash contents of adzuki bean with drainage methods were 10.10~11.60, 14.13~21.75, 0.02~0.73 and 2.81~3.45 g/100 g, respectively. The total polyphenol, flavonoid and tannin contents, and radical scavenging activity of adzuki bean showed significant differences by drainage methods. The total polyphenol, flavonoid, and tannin contents by drainage methods were 2.73~4.14 mg GAE/g, 1.07~1.43 mg CE/g, and 1.27~1.84 mg TAE/g, respectively. The DPPH and ABTS radical scavenging activities were 2.84~4.47 and 5.11~6.74 mg TE/g, respectively. The antioxidant compounds and radical scavenging activity of the adzuki bean by drainage methods were frequently affected soil water.

Variation of Copper Content in Paddy Soil and Rice from Janghang Smelter Area (장항제련소 지역의 논토양과 수도체중 Cu 함량의 변화에 관한 연구)

  • Kim, Seong-Jo;Lee, Man-Sang;Ryu, Taek-Kyu;Yang, Chang-Hyu;Moon, Kwang-Hyun;Baek, Seung-Hwa
    • Korean Journal of Environmental Agriculture
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    • v.13 no.1
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    • pp.1-9
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    • 1994
  • To investigate differences in Cu contents in paddy soils and rices, being affected by air pollutants from the Janghang Smelter, soil samples at the different directions and surface (0-15cm) and subsurface (15-30cm) were collected in 1982 and 1990, and rice plants at the soil corresponding sampling sites in 1990 were also at separately collected from the Janghang Smelter area. Soil samples were extracted with $4M-HNO_3$ and plant samples were digested with a mixture of $HNO_3$ and $HClO_4$ for analyzing Cu, Zn, Cd and Pb by atomic absorption spectrophotometry. The Cu contents in soils ranged from 5.1 to 391.0 mg $kg^{-1}$. The average content of Cu in 1990 was higher than that in 1982. The Cu content in soils nearer to the center of the smelter was higher than that farther from the center. The Cu content was highest at the east direction, and was in order of east > north-north east = north east > north. The variation of Cu levels in soil at east sites was more considerable than other directions. The Cu level in surface soils was higher than that in subsurface soils. The Cu contaminated area was within 5 km at east, and 3 km at north-north east and north east. A significant correlation was found between Cu content in surface soils of 1982 and that in surface and subsurface soils of 1990, and between Cu content in soils and soil properties such as organic matter(OM), available phosphate, available silicate, exchangeable $Ca^{++}$ and $Na^+$ in 1982. The Cu content in brown rice ranged from 0.4 to 3.6 mg $kg^{-1}$, and was the lowest in parts of rice plant, and Cu content in a part of plant was 13.75 times higher than that in brown rice. The Cu content of leaf sheath, stem and brown rice was correlated with the levels of Cd, Zn, Cu and Pb in soils. The Cu content in soil regardless of years and soil depths was correlated with Zn and Pb in soil in the area affected by waste gas.

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