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COMBUSTION VISUALIZATION AND EMISSIONS OF A DIRECT INJECTION COMPRESSION IGNITION ENGINE FUELED WITH BIO-DIESOHOL

  • LU X.;HUANG Z.;ZHANG W.;LI D.
    • International Journal of Automotive Technology
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    • v.6 no.1
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    • pp.15-21
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    • 2005
  • The purpose of this paper is to experimentally investigate the engine pollutant emissions and combustion characteristics of diesel engine fueled with ethanol-diesel blended fuel (bio-diesohol). The experiments were performed on a single-cylinder DI diesel engine. Two blend fuels were consisted of $15\%$ ethanol, $83.5\%$ diesel and $1.5\%$ solublizer (by volume) were evaluated: one without cetane improver (E15-D) and one with a cetane improver (E15-D+CN improver). The engine performance parameters and emissions including fuel consumption, exhaust temperature, lubricating oil temperature, Bosch smoke number, CO, NOx, and THC were measured, and compared to the baseline diesel fuel. In order to gain insight into the combustion characteristics of bio-diesohol blends, the engine combustion processes for blended fuels and diesel fuel were observed using an Engine Video System (AVL 513). The results showed that the brake specific fuel consumption (BSFC) increased at overall engine operating conditions, but it is worth noting that the brake thermal efficiency (BTE) increased by up to $1-2.3\%$ with two blends when compared to diesel fuel. It is found that the engine fueled with ethanol-diesel blend fuels has higher emissions of THC, lower emissions of CO, NOx, and smoke. And the results also indicated that the cetane improver has positive effects on CO and NOx emissions, but negative effect on THC emission. Based on engine combustion visualization, it is found that ignition delay increased, combustion duration and the luminosity of flame decreased for the diesohol blends. The combustion is improved when the CN improver was added to the blend fuel.

Expression of the Promoter for the Maltogenic Amylase Gene in Bacillus subtilis 168

  • Kim Do-Yeon;Cha Choon-Hwan;Oh Wan-Seok;Yoon Young-Jun;Kim Jung-Wan
    • Journal of Microbiology
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    • v.42 no.4
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    • pp.319-327
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    • 2004
  • An additional amylase, besides the typical $\alpha-amylase,$ was detected for the first time in the cytoplasm of B. subtilis SUH4-2, an isolate from Korean soil. The corresponding gene (bbmA) encoded a malto­genic amylase (MAase) and its sequence was almost identical to the yvdF gene of B. subtilis 168, whose function was unknown. Southern blot analysis using bbmA as the probe indicated that this gene was ubiquitous among various B. subtilis strains. In an effort to understand the physiological function of the bbmA gene in B. subtilis, the expression pattern of the gene was monitored by measuring the $\beta-galactosidase$ activity produced from the bbmA promoter fused to the amino terminus of the lacZ struc­tural gene, which was then integrated into the amyE locus on the B. subtilis 168 chromosome. The pro­moter was induced during the mid-log phase and fully expressed at the early stationary phase in defined media containing $\beta--cyclodextrin\;(\beta-CD),$ maltose, or starch. On the other hand, it was kept repressed in the presence of glucose, fructose, sucrose, or glycerol, suggesting that catabolite repression might be involved in the expression of the gene. Production of the $\beta-CD$ hydrolyzing activity was impaired by the spo0A mutation in B. subtilis 168, indicating the involvement of an additional regu­latory system exerting control on the promoter. Inactivation of yvdF resulted in a significant decrease of the $\beta-CD$ hydrolyzing activity, if not all. This result implied the presence of an additional enzyme(s) that is capable of hydrolyzing $\beta-CD$ in B. subtilis 168. Based on the results, MAase encoded by bbmA is likely to be involved in maltose and $\beta-CD$ utilization when other sugars, which are readily usable as an energy source, are not available during the stationary phase.

Application of Recent DNA/RNA-based Techniques in Rumen Ecology

  • McSweeney, C.S.;Denman, S.E.;Wright, A.-D.G.;Yu, Z.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.2
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    • pp.283-294
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    • 2007
  • Conventional culture-based methods of enumerating rumen microorganisms (bacteria, archaea, protozoa, and fungi) are being rapidly replaced by nucleic acid-based techniques which can be used to characterise complex microbial communities without incubation. The foundation of these techniques is 16S/18S rDNA sequence analysis which has provided a phylogenetically based classification scheme for enumeration and identification of microbial community members. While these analyses are very informative for determining the composition of the microbial community and monitoring changes in population size, they can only infer function based on these observations. The next step in functional analysis of the ecosystem is to measure how specific and, or, predominant members of the ecosystem are operating and interacting with other groups. It is also apparent that techniques which optimise the analysis of complex microbial communities rather than the detection of single organisms will need to address the issues of high throughput analysis using many primers/probes in a single sample. Nearly all the molecular ecological techniques are dependant upon the efficient extraction of high quality DNA/RNA representing the diversity of ruminal microbial communities. Recent reviews and technical manuals written on the subject of molecular microbial ecology of animals provide a broad perspective of the variety of techniques available and their potential application in the field of animal science which is beyond the scope of this treatise. This paper will focus on nucleic acid based molecular methods which have recently been developed for studying major functional groups (cellulolytic bacteria, protozoa, fungi and methanogens) of microorganisms that are important in nutritional studies, as well as, novel methods for studying microbial diversity and function from a genomics perspective.

Treatment of Talipes Equinus Deformity Using Free Radial Forearm Flap and Achilles Tendon Lengthening (아킬레스건 신장술과 유리 전완부 피판술을 이용한 첨족 장애의 치료)

  • Kim, Dae Seung;Lee, Jong Wook;Ko, Jang Hyu;Seo, Dong Kook;Choi, Jai Ku;Jang, Young Chul;Oh, Suk Joon
    • Archives of Plastic Surgery
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    • v.34 no.5
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    • pp.593-598
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    • 2007
  • Purpose: Talipes equinus deformity is defined as impossibility of heel weight-bearing and lacking of improvement of toe-tip gait despite sufficient duration of conservative treatment. The incidence of equinus deformity induces post-traumatic extensive soft tissue defect and subsequently increases it. Severe equinus deformities of the foot associated with extensive scarring of the leg and ankle were corrected using achilles Z-lengthening and free-tissue transfer. Methods: Free radial forearm flap was done in nine cases of eight patients from January 2000 to November 2006. Causes of deformity were post-traumatic contracture (one patient) and post-burn scar contracture (seven patients). Seven patients were male, one patient was female. Mean age was 32.1 (range, 10-57). Flap donors were covered with artificial dermis ($Terudermis^{(R)}$) and split thickness skin graft (five cases), and medium thickness skin graft only (four cases). Results: The size of flaps varied from $6{\times}12$ to $15{\times}12cm$ (average, $12{\times}7.8cm$). Achilles tendon was lengthened 4.2cm on average. Free radial forearm flap was satisfactory in all cases. All patients could ambulate normally after the surgery. Cases having donor coverage with $Terudermis^{(R)}$ were aesthetically better than those having skin grafts only. Conclusion: This study suggested that severe equinus deformities associated with extensive scarring of the leg and ankle can be corrected effectively free radial forearm flap and Achilles tendon lengthening.

Characterization and Regulation of the Gene Encoding Monothiol Glutaredoxin 3 in the Fission Yeast Schizosaccharomyces pombe

  • Moon, Jeong-Su;Lim, Hye-Won;Park, Eun-Hee;Lim, Chang-Jin
    • Molecules and Cells
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    • v.20 no.1
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    • pp.74-82
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    • 2005
  • Glutaredoxins (Grxs) are thioloxidoreductases which are required for maintaining thiol/disulfide equilibrium in living cells. The Grx3 gene, which encodes one of the three monothiol Grxs in the fission yeast Schizosaccharomyces pombe, was characterized, and its transcriptional regulation studied. Genomic DNA encoding Grx3 was isolated by PCR, and a plasmid pTT3 carrying this DNA was produced. The DNA sequence has 1,267 bp, which would encode a monothiol Grx of 166 amino acids with a molecular mass of 18.3 kDa. The putative protein has 27% homology with Grx5, and contains many hydrophobic amino acid residues in its N-terminal region. S. pombe cells harboring pTT3 had increased Grx activity and enhanced survival on minimal medium plates containing aluminum (5 mM), BSO (0.05 mM), menadione (0.01 mM) or cadmium (0.2 mM). The 568 bp upstream region of Grx3 was fused into the promoterless b-galactosidase gene of the shuttle vector YEp367R to generate fusion plasmid pMJS10. Potassium chloride (KCl) and metals including aluminum and cadmium enhanced the synthesis of ${\beta}$-galactosidase from the fusion gene. The synthesis of ${\beta}$-galactosidase was also enhanced, in a Pap1-dependent manner, by fermentable carbon sources such as glucose (at low concentrations) and sucrose, but not by non-fermentable carbon sources such as ethanol and acetate. Grx3 mRNA increased in response to treatment with BSO. These observations indicate that S. pombe Grx3 is involved in the response to stress, and is regulated by stress.

Interaction of Beef Growth Type${\times}$Production System for Carcass Traits of Steers

  • Brown , A.H. Jr.;Camfield, P.K.;Johnson, Z.B.;Rakes, L.Y.;Pohlman, F.W.;Brown, C.J.;Sandelin, B.A.;Baublits, R.T.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.2
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    • pp.259-266
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    • 2005
  • Steers (n=335) of known genetic backgrounds from four fundamentally different growth types were subjected to two production systems to study differences in carcass traits. Growth types were animals with genetic potential for large mature weight-late maturing, intermediate mature weight-late maturing, intermediate mature weight-early maturing and small mature weight-early maturing. Each year, in a nine-year study, calves of each growth type were weaned and five steers of each growth type were developed on pasture or feedlot and slaughtered at approximately 20 and 14 months of age, respectively. Data collected were pre-slaughter shrunk body weight (SBW); hot carcass weight (HCW); dressing percentage (DRESS); fat thickness at the $12^{th}$ and $13^{th}$ rib interface (FAT); percentage kidney, pelvic, and heart fat (KPH); longissimus muscle area (LMA); marbling score (MARB); quality grade (QG); and yield grade (YG). Year and growth type were significant for all carcass traits. The growth type${\times}$production system interaction was an important source of variation in SBW, HCW; FAT, YG and MARB. The same interaction was non-significant for DRESS, KPH, LMA and QG. Carcass differences in measures of fatness were greater in the feedlot system than in the pasture system. These data could aid producers in matching beef growth type to the production system most suitable for efficient use of resources.

Development and Evaluation of a Patient Safety-focused Inservice Education Program for Surgical Nurse (외과계 간호사를 위한 환자안전 관점의 실무교육 프로그램 개발과 효과)

  • Kim, Young-Mee;You, Myung-Sook;Cho, Yaun-Hee;Park, Seung-Hee;Nam, Seung-Nam;Park, Mi-Ok;Kim, Se-Young;Kim, Min-Young
    • Journal of Korean Academy of Nursing Administration
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    • v.16 no.2
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    • pp.152-161
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    • 2010
  • Purpose: The aim of this project was to develop a patient safety-focused inservice education program for surgical nurse and to test the effects of this program. Methods: Methodological designs for instruments development, a pretest-posttest and a posttest design were employed. After the education, nurses' satisfaction, confidence, usefulness and application of 137 nurses were evaluated at 15 surgical units of a tertiary teaching hospital in Seoul, Korea. The education contents are 6 skill areas (infusion pump use, suction, chest tube drainage, oxygen administration, nebulizer use, insulin administration) and medication knowledge. Teaching methods were lecture, instructor demonstration, and 1:1 skill test. Descriptive statistics, Wilcoxon test, Spearman's correlation and Stepwise regression were used. Results: Satisfaction scores for skills and medication education were 4.00-4.21 (out of 5), The more performance frequency in 6 skills, the higher score in confidence as well as in usefulness and application, and the higher satisfaction with the program, the higher score in usefulness, application, confidence, and medication knowledge. Medication knowledge improved after the education (Z=-7,757, p<.001). Significant predictors of skill confidence were application of skills in job performance, medication confidence, and career in present unit. Conclusion: The results of this study suggest that systematic and continuous inservice education will improve patient safety by promoting nursing quality.

The Effect of Pre-Heat Treatment Parameters on the Ion Nitriding of Tool Steel (금형공구강의 이온질화에 미치는 이전열처리 조건의 영향)

  • Lee, J.S.;Kim, H.G.;You, Y.Z.
    • Journal of the Korean Society for Heat Treatment
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    • v.14 no.1
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    • pp.27-34
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    • 2001
  • The effects of pre-heat treatment(Q/T) on microstructure and hardness of STD11 and STD61 tool steel nitrided by micro-pulse plasma were investigated. The quenching temperature for obtaining matrix hardness of STD11 and STD61 steel on range of HRC 50 to HRC 60 desired for machine parts is about $1070^{\circ}C$ and $1020^{\circ}C$ respectively. The hardness of STD11 and STD61 quenched at the temperature was HRC 63 and HRC 56 respectively. The nitrided case depth of STD11 and STD61 nitrided at $550^{\circ}C$ for 5 hours was independent of pre-heat treatment condition and the depth was approximately $100{\mu}m$. However, hardness and compactness of nitrided layer on Q/T treated specimen were higher than the annealed specimen. The case depth increased linearly with the increase of nitriding temperature, however, the hardness of nitrided layer decreased with the increase of temperature. Phase mixture of ${\gamma}-Fe_4N$ and ${\varepsilon}-Fe_{2-3}N$ was detected by XRD analysis in the nitrided layer formed at the optimum nitriding condition. The optimum nitriding temperature was approximately $490^{\circ}C$ which was $10^{\circ}C$ lower than the tempering temperature for preventing softening behavior of STD11 and STD61 matrix during nitriding process and the surface hardness of nitrided layer obtained by optimum pre-heat treatment condition was about Hv1400.

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Assessment of Inhabitation and Species Diversity of Fish to Substrate Size in the Geum River Basin (금강수계에서 하상재료에 따른 어류의 종다양성 및 서식지 평가)

  • Hur, Jun Wook;In, Dong Soo;Jang, Min Ho;Kang, Hyoengsik;Kang, Kyoung Ho
    • Journal of Environmental Impact Assessment
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    • v.20 no.6
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    • pp.845-856
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    • 2011
  • In order to establish fundamental data for stream restoration and environmental flow, we investigated inhabitation and species diversity of fish to substrate size in the typical streams of Geum River Basin. Field monitoring including fish sampling was conducted from October 2007 to October 2009. Substrate size was determined according to six different : silt (Si), sand (Sa), fine gravel (Fg), coarse gravel (Cg), cobbles (Co) and boulders (Bo). A total number of fish caught in the 18 sites was 7,649 representing 10 families 50 species, and Si, Sa, Fg, Cg, Co and Bo stations occupied 30, 29, 38, 30, 27 and 17 species, respectively. The most frequently found species in number was pale chum (Zacco platypus, 29.7%, n=2,275) followed by Z. koreanus (22.5%, n=1,720) in total stations. Biological diversity with increase of substrate size from the dominance of part species showed higher values as dominance index, lower and diversity, richness and evenness index. Index of biological integrity (IBI) and qualitative habitat evaluation index (QHEI) scores decreased with increase of substrate size. Therefore, it is necessary to make an effort on stream rehabilitation with evaluation of physical habitat condition by indicator species in order to maintain biodiversity and perform ecological restoration.

Fish Fauna in the Seomjin River, Korea (섬진강의 어류상)

  • Park, Se Kwon;Joo, Hyun Soo
    • Korean Journal of Environmental Biology
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    • v.33 no.3
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    • pp.314-329
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    • 2015
  • The fish fauna was investigated from 2010 and 2013 at main stream and tributaries in the Seomjin River which has no estuary dike. The collected fishes were identified into 37,751 individuals of 107 species of 81 genera belonging to 41 families. Among the collected fishes the primary freshwater fishes were 57 species (Relative Abundance: 53.3%), the secondary fishes were 10 species (RA: 9.3%) and the marine fishes were 40 species (RA: 37.4%). The dominant species was Zacco platypus (RA: 28.7%), and the subdominant species was Zacco koreanus (RA: 15.0%). The endemic species were 21 species (RA: 31.3%). The endangered fishes were Acheilognathus somjinensis (Level I), Lampetra reissneri (Level II) and Microphysogobio koreensis (Level II). The exotic species were Carassius cuvieri, Lepomis macrochirus and Micropterus salmoides. We supposed that Odontobutis interrupta in the Seomjin River is translocated species.