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천연망간산화물에 의한 클로로페놀의 산화결합생성물을 매개로 한 다환방향족화합물(PAH) 오염물의 고정화 효과 (Enhancement of Phenanthrene Sorption Rate on Natural Manganese Oxide Using the Oxidative Coupling Reaction of Phenanthrene)

  • 전선영;박재우;신원식;고석오
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제10권5호
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    • pp.45-51
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    • 2005
  • 본 연구에서는 다환방형족화합물의 하나인 phenanthrene를 이용하여 천연망간산화물에 흡착/탈착되는 특성을 평가하였다. 토양, 퇴적물이나 수체에 다양한 오염물이 동시에 존재하는 경우를 고려하여 페놀계 오염물이 있는 경우, 다환 방형족화합물의 흡탈착에 미치는 영향을 조사하였다. 망간산화물에 의하여 4-클로로페놀은 효과적으로 산화되었으며 반응산물은 고분자화(휴믹화) 되는 경향을 나타내었다. 4-클로로페놀이 분해됨에 따라 망간산화물 표면에 흡착되는 phenanthrene의 양은 급격히 증가하였다. 또한, 4-클로로페놀이 존재하는 경우 흡착된 phenanthrene의 탈착에 대한 저항성은 4-클로로페놀 농도가 증가할수록 강하게 나타남으로써 고분자화된 4-클로로페놀 반응산물에 phenanthrene이 강하게 흡착되어 있다는 결과를 도출하였다. 결과적으로 망간산화물은 페놀계 오염물과 다환방향족화합물을 동시에 처리하는데 효과적으로 사용될 수 있음을 보여주었다.

$\cdot$노년 당뇨병여성의 아연영양상태와 비만도와의 관련성 (Relationship between Zinc Status and Obesity of Type 2 Diabetic Women)

  • 이정희;이희자;이인규;윤진숙
    • 대한지역사회영양학회지
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    • 제10권1호
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    • pp.70-78
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    • 2005
  • Zinc is known to have important effects on insulin activity and to increase the body fat deposition. The purpose of this study was to investigate the zinc status and obesity in 50 type 2 diabetic women visiting public health center and hospital. The mean age was 57.9 $\pm$ 6.9 years old. The mean of diabetic duration was 8.0 $\pm$ 6.5 years. Body mass index (BMI) of diabetes was $23.2 \pm 2.3 kg/m^2$. There were no significant differences of mean age, anthropometric indices, and insulin level other than fasting blood sugar (p < 0.001) and insulin resistance (p < 0.00l) between diabetes and control group. The obesity ratio of diabetes was $20\%$, $66\%$ and $84\%$ for BMI, waist circumference and waist/hip ratio (WHR), respectively. Plasma zinc level was not significantly different between diabetes and control group. However, urinary zinc excretion of diabetes was approximately twice of control group (p < 0.001). Urinary zinc loss was fivefold higher in the hyperglycemia ($HbA_{lc}> 10\%$) than in normal blood glucose (p < 0.001). Anthropometric indices were decreased in hyperglycemia. On the other hand, there were the tendency of increased urinary zinc in obese group for waist circumference and percent of body fat. These results suggested that controlled normal blood glucose could improve hyperzincuria and anthropometric changes in type 2 women diabeties.

돼지 액상정액 내 세균오염과 항생제 감수성에 관한 연구 (Characterization of Bacteria and Their Antibiotic Sensitivities in Porcine Liquid Semen)

  • 유재원;조규호;홍준기;김명직;박준철;정일병;김인철
    • Journal of Animal Science and Technology
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    • 제50권6호
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    • pp.793-798
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    • 2008
  • 정액 내 세균오염 종류와 검출 빈도를 조사한 결과는 Table 1에서 보는 바와 같다. 돼지 정액 내 오염세균 중 검출빈도는 Staphylo- coccus genus, Proteus genus, Bacillus genus, Pasteulla genus, Acinetobacte genus 및 Serratia genus 등의 순으로 나타났다. 동정된 세균 중 33종의 세균에 대하여 디스크법을 이용하여 8종의 항생제에 대한 감수성을 조사 한 결과는 Table 2와 3에서 보는 바와 같다. 검출된 세균의 항생제 감수성을 조사한 결과 항생제 감수성이 높은 항생제는 Amikacin, Polymyxin B, Neomycin, Streptomycin, Kanamycin, Tetracycline, Erythromycin 및 Penicillin순 이었다. Enterococcus faecium와 Streptococcus uberis는 Streptomycin을 제외한 모든 항생제에 대하여 저항성이 있는 것으로 조사되었다.

Amplitude dependency of damping of tall structures by the random decrement technique

  • Xu, An;Xie, Zhuangning;Gu, Ming;Wu, Jiurong
    • Wind and Structures
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    • 제21권2호
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    • pp.159-182
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    • 2015
  • This study focuses on the amplitude dependency of damping of tall structures by the random decrement technique (RDT). Many researchers have adopted RDT to establish the amplitude dependency of damping ratios in super-tall buildings under strong wind loads. In this study, a series of simulated examples were analyzed to examine the reliability of this method. Results show that damping ratios increase as vibration amplitudes increase in several cases; however, the damping ratios in the simulated signals were preset as constants. This finding reveals that this method and the derived amplitude-dependent damping ratio characteristics are unreliable. Moreover, this method would obviously yield misleading results if the simulated signals contain Gaussian white noise. Full-scale measurements on a super-tall building were conducted during four typhoons, and the recorded data were analyzed to observe the amplitude dependency of damping ratio. Relatively wide scatter is observed in the resulting damping ratios, and the damping ratios do not appear to have an obvious nonlinear relationship with vibration amplitude. Numerical simulation and field measurement results indicate that the widely-used method for establishing the amplitude-dependent damping characteristics of super-tall buildings and the conclusions derived from it might be questionable at the least. More field-measured data must be collected under strong wind loads, and the damping characteristics of super-tall buildings should be investigated further.

연속철근콘크리트(CRCP) 종방향 철근의 초기거동 분석 (Analysis of Longitudinal Steel Behaviors of Continuously Reinforced Concrete Pavement at Early Age)

  • 남정희;전성일
    • 한국도로학회논문집
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    • 제16권6호
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    • pp.59-67
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    • 2014
  • PURPOSES : The purpose of this study is to analyse the longitudinal steel strain and stress of continuously reinforced concrete pavement(CRCP) with longitudinal and transverse direction at early age using stress dependent strain analysis method. METHODS : To measure the longitudinal steel strain, 9-electrical resistance and self-temperature compensation gauges were installed to CRCP test section (thickness = 250mm, steel ratio = 0.7%) and continuously measured 10min. intervals during 30days. In order to properly analyze the steel stress first, temperature compensation process has been conducted. Secondly, measured steel strains were divided into stress dependent strain (elastic strain) and stress independent strain (thermal strain) and then stress dependent strain was applied to stress calculation of longitudinal steels. RESULTS : Steel strains were successfully measured during 30days. To verify the accuracy of temperature compensation process, measured coefficient of thermal expansion(COTE,$11.46{\times}10^{-6}m/m/^{\circ}C$) of longitudinal steel before paving was compared with that of unrestrained steel. Max. steel stress in the transverse direction shows about 266MPa at 23days after placement. CONCLUSIONS : Steel stresses in the longitudinal and transverse direction have been evaluated. In longitudinal direction, steel stress from the crack was rapidly reduced from 183MPa at crack to 18MPa from 600mm apart the crack. From this observation, stress effective length can be identified as within 600mm apart from the crack. In transverse direction, max. stress point was located near the center of pavement width and stress level(266MPa) is about 66% of yield stress of steel.

Gene Microarray Analysis for Porcine Adipose Tissue: Comparison of Gene Expression between Chinese Xiang Pig and Large White

  • Guo, W.;Wang, S.H.;Cao, H.J.;Xu, K.;Zhang, J.;Du, Z.L.;Lu, W.;Feng, J.D.;Li, N.;Wu, C.H.;Zhang, L.
    • Asian-Australasian Journal of Animal Sciences
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    • 제21권1호
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    • pp.11-18
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    • 2008
  • We created a cDNA microarray representing approximately 3,500 pig genes for functional genomic studies. The array elements were selected from 6,494 cDNA clones identified in a large-scale expressed sequence tag (EST) project. These cDNA clones came from normalized and subtracted porcine adipose tissue cDNA libraries. Sequence similarity searches of the 3,426 ESTs represented on the array using BLASTN identified 2,790 (81.4%) as putative human orthologs, with the remainder consisting of "novel" genes or highly divergent orthologs. We used the gene microarray to profile transcripts expressed by adipose tissue of fatty Chinese Xiang pig (XP) and muscley Large White (LW). Microarray analysis of RNA extracted from adipose tissue of fatty XP and muscley LW identified 81 genes that were differently expressed two fold or more. Transcriptional differences of four of these genes, adipocyte fatty acid binding protein (aP2), stearyl-CoA desaturase (SCD), sterol regulatory element binding transcription factor 1 (SREBF1) and lipoprotein lipase (LPL) were confirmed using SYBR Green quantitative RT-PCR technology. Our results showed that high expression of SCD and SREBF1 may be one of the reasons that larger fat deposits are observed in the XP. In addition, our findings also illustrate the potential power of microarrays for understanding the molecular mechanisms of porcine development, disease resistance, nutrition, fertility and production traits.

Effects of Uncaria rhynchophylla Extracts on Differentiation and Bone Mineralized Formation in Human Osteoblast-like SaOS-2 cells

  • Huh, Jeong-Eun;Baek, Yong-Hyeon;Choi, Do-Young;Lee, Jae-Dong;Park, Dong-Suk
    • 대한한의학회지
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    • 제28권4호
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    • pp.158-167
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    • 2007
  • Background & Objective : Uncaria rhynchophylla is traditional medicine herb used for enhancing body resistance against various diseases. The aim of this study was to identify if Uncaria rhynchophylla extracts induce osteogenic activity in human osteoblast-like SaOS-2 cells. Methods : The osteogenic activity of Uncaria rhynchophylla was evaluated on cell proliferation assay by WST-8, and osteoblast-specific genes, such as VEGF, type I collagen (Col I), osteocalcin (OCN), and osteopontin (OPN) by RT-PCR analysis and ELISA assay in osteoblasts-like SaOS-2 cells. Bone mineralization was stained with Alizalin red method. Results : Uncaria rhynchophylla had significantly increased cell proliferation at a dose dependent manner in human osteoblast-like SaOS-2 cells. Uncaria rhynchophylla markedly increased alkaline phosphatase (ALP), vascular endothelial growth factor (VEGF) mRNA expression at 7 days and dose dependently increased ALP activity and VEGF secretion in human osteoblast-like SaOS-2 cells. Also, Uncaria rhynchophylla time-dependently increased type I collagen (Col I), osteopontin (OPN), and osteocalcin (OCN) mRNA in SaOS-2 cells. Extracellular accumulation of proteins such as Col I and OCN was maximal increased by Uncaria rhynchophylla at 10 ${\mu}g/ml$. Also, Uncaria rhynchophylla significantly induced mineralization in the culture of SaOS-2 cells. Conclusion : This study showed that Uncaria rhynchophylla had enhanced proliferation, ALP activity, VEGF, bone matrix proteins such as OCN, OPN, and Col I, and mineralization in SaOS-2 cells. These results propose that Uncaria rhynchophylla can play an important role in osteoblastic bone formation, osteogenesis, and may possibly lead to the development of bone-forming drugs.

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사고각에 따른 자속구속형 전류제한기의 전류제한특성 (Current Limiting Characteristics of Flux-Lock Type High-TC Superconducting Fault Current Limiter According to Fault Angles)

  • 박형민;임성훈;조용선;박충렬;한병성;최효상;현옥배
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.12-14
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    • 2004
  • We investigated current limiting characteristics of the flux-lock type high-Tc superconcting fault current limiter(HTSC-FCL) according to fault angles. The Flux-lock type HTSC-FCL consists of primary and the secondary copper coils that are wound in parallel each other through the iron core and YBCO thin flim. In this paper, the current limiting characteristics of the flux-lock type HTSC-FCL according to fault angles in case of the subtractive and additive polarity windings were compared and analyzed. From the results, the flux-lock type HTSC-FCL could limit more quickly fault current as the fault angles increased irrespective of the fault angles. On the other hand, the initial power burden of HTSC element after a fault happened increased as the fault angles increased. In addition, it was confirmed that the resistance of flux-lock type HTSC-FCL in case of subtractive polarity winding was more increased than that of additive polarity winding and that the peak current of fault current in case of subtractive polarity winding was larger than that of the additive polarity winding case.

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Pathway Analysis of Metabolic Syndrome Using a Genome-Wide Association Study of Korea Associated Resource (KARE) Cohorts

  • Shim, Unjin;Kim, Han-Na;Sung, Yeon-Ah;Kim, Hyung-Lae
    • Genomics & Informatics
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    • 제12권4호
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    • pp.195-202
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    • 2014
  • Metabolic syndrome (MetS) is a complex disorder related to insulin resistance, obesity, and inflammation. Genetic and environmental factors also contribute to the development of MetS, and through genome-wide association studies (GWASs), important susceptibility loci have been identified. However, GWASs focus more on individual single-nucleotide polymorphisms (SNPs), explaining only a small portion of genetic heritability. To overcome this limitation, pathway analyses are being applied to GWAS datasets. The aim of this study is to elucidate the biological pathways involved in the pathogenesis of MetS through pathway analysis. Cohort data from the Korea Associated Resource (KARE) was used for analysis, which include 8,842 individuals (age, $52.2{\pm}8.9years$ ; body mass index, $24.6{\pm}3.2kg/m^2$). A total of 312,121 autosomal SNPs were obtained after quality control. Pathway analysis was conducted using Meta-analysis Gene-Set Enrichment of Variant Associations (MAGENTA) to discover the biological pathways associated with MetS. In the discovery phase, SNPs from chromosome 12, including rs11066280, rs2074356, and rs12229654, were associated with MetS (p < $5{\times}10^{-6}$), and rs11066280 satisfied the Bonferroni-corrected cutoff (unadjusted p < $1.38{\times}10^{-7}$, Bonferroni-adjusted p < 0.05). Through pathway analysis, biological pathways, including electron carrier activity, signaling by platelet-derived growth factor (PDGF), the mitogen-activated protein kinase kinase kinase cascade, PDGF binding, peroxisome proliferator-activated receptor (PPAR) signaling, and DNA repair, were associated with MetS. Through pathway analysis of MetS, pathways related with PDGF, mitogen-activated protein kinase, and PPAR signaling, as well as nucleic acid binding, protein secretion, and DNA repair, were identified. Further studies will be needed to clarify the genetic pathogenesis leading to MetS.

실리콘 아크릴레이트를 함유하고 있는 코팅필름의 물성 (Properties of Coating Film Containing Silicone acrylate)

  • 이봉우;방문수;홍진후;김대준;김현중
    • 접착 및 계면
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    • 제3권4호
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    • pp.10-18
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    • 2002
  • 오늘날 플라스틱은 많은 분야에서 매우 중요한 역할을 하고 있으며, 플라스틱의 표면개질을 통해 경도, 마모, 내화학성과 같은 성질을 개선하여 성능을 향상시킬 수 있다. 본 연구의 목적은 polycarbonate, polymethylmethacrylate, acrylonitrilebutadienestyrene과 같은 플라스틱에 적용되는 기능성 하드코팅제를 개발하기 위한 것이다. 하드코팅제를 개발하기 위하여 먼저 실리콘아크릴레이트 올리고머(SAOE)를 합성하고, 이를 함유한 코팅필름을 PC 기재로 하였으며, 도막은 자외선경화에 의하였다. 실험의 결과에 의하면, SAOE를 함유하고 있는 도막의 물성이 SAOE를 함유하고 있지 않은 도막의 물성에 비해서 크게 향상되었다. 특히 코팅 조성물내에 1wt%의 SAOE가 함유되었을 때, 이로부터 얻어진 도막의 경도나 광택이 가장 우수함을 나타내었다.

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