• 제목/요약/키워드: synergistic

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이중동축류 화염을 이용한 혼합연료의 매연생성 특성에 관한 연구 (Soot Formation Characteristics of Concentric Diffusion Flames with Mixture Fuels)

  • 이원남;남연우
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2002년도 제25회 KOSCI SYMPOSIUM 논문집
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    • pp.123-128
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    • 2002
  • 이중동축류 버너를 사용하여 에틸렌/프로판 및 에틸렌/메탄 혼합 연료의 매연생성 상승효과와 관련된 매연생성 메커니즘을 이해하기 위한 실험을 수행하였다. 매연체적분율, 광산란신호 및 PAH 형광신호를 측정한 결과 다음을 알 수 있었다. 에틸렌/프로판 혼합연료에서 연료공급 위치의 변화에 따른 매연생성특성의 변화는 대부분 synergistic 효과와 관련되는 것임을 알 수 있었다. 그러나 에틸렌/메탄 혼합연료의 경우 연료공급의 위치변화가 매연생성에 크게 영향을 주지 않았다. PAH 분포는 synergistic 효과에 의한 매연 생성 특성의 변화와 일관성이 없는 것이 관찰되었다. 따라서 synergistic 효과에 대한 PAH의 역할에 대한 이해가 필요함을 알 수 있었다.

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Synergistic Antifungal Activity of Phellodendri Cortex and Magnoliae Cortex against Candida albicans

  • NA, Hyunjeong;KIM, Tae-Jong
    • Journal of the Korean Wood Science and Technology
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    • 제50권1호
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    • pp.12-30
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    • 2022
  • Many studies on plant extracts have been reported for the treatment of candidiasis caused by Candida albicans, a representative fungal infection. This study demonstrates the synergistic antifungal activity of the combination of Phellodendri Cortex and Magnoliae Cortex, previously reported to have antifungal efficacy. Considering the antifungal efficacy and the separation of the active constituents, berberine and magnolol, hot water extraction and carbon dioxide supercritical extraction were selected for Phellodendri Cortex and Magnoliae Cortex, respectively. A combination of 0.55 g/L hot water extract of Phellodendri Cortex and 0.59 g/L carbon dioxide supercritical extract of Magnoliae Cortex showed synergistic antifungal activity. The synergistic antifungal activity of 160 μM berberine and 100 μM magnolol, which are representative antifungal compounds of Phellodendri Cortex and Magnoliae Cortex, respectively, contributes to the synergistic antifungal effect of their extracts. The additive decrease in cellular ergosterol level and the increased antifungal efficacy by extracellular ergosterol suggest that disruption of the biological function of ergosterol in the cell membrane is not responsible for the synergistic antifungal activity of berberine and magnolol. Synergistic cellular release of chromosomal DNA upon mixing berberine and magnolol indicates that disruption of the cellular structure is responsible for the synergistic antifungal effect of berberine and magnolol.

Rosemary, Sage, Oregano와 Ginger의 메탄올과 헥산 추출물의 항산화 작용에 대한 카테킨과 아스코르브산의 상승 효과 (Synergistic Effects of Catechin or Ascorbic Acid on Antioxidative Activities of Hexane and Methanol Extracts from Rosemary, Sage, Oregano, and Ginger)

  • 안채경;한대석;이영경;이영철
    • 한국식품영양과학회지
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    • 제34권5호
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    • pp.586-592
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    • 2005
  • 역마이셀 미강유를 기질로 하여 rosemary, sage, oregano와 ginger의 메탄올과 헥산 추출물 500ppm에 카테킨 또는 아스코르브산 200 ppm을 각각 첨가하여 Rancimat으로 유도기간을 측정하여 항산화 상승효과를 조사하였다. Rosemary, sage, oregano와 ginger의 메탄을 추출물에 카테킨 첨가시 모두 상승효과를 나타내었으며, 아스코르브산을 첨가시 ginger를 제외하고는 항산화 상승효과를 보였다. 항산화 상승효과는 전반적으로 아스코르브산보다 카테킨이 높게 나타났다. 헥산 추출물의 경우, 카테킨 첨가시 oregano와 ginger에서 강한 상승효과를 보였으며, ascorbic acid 첨가시, rosemary와 sage에서 상승효과가 나타났다.

Synergistic Extraction of Palladium(Ⅱ) with Thenoyltrifloroacetone and Tri-n-octylphosphine Oxide

  • 이상호;정구순
    • Bulletin of the Korean Chemical Society
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    • 제16권6호
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    • pp.479-483
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    • 1995
  • The synergistic extraction of palladium(Ⅱ) was studied with 1,2-dichloroethane containing thenoyltrifluoroacetone (TTA; HA) and tri-n-octylphosphine oxide (TOPO; S). The main composition of synergistic adduct extracted into 1,2-dichloroethane phase was found to be PdA2S2. The equilibrium constants of the synergistic reaction were calculated. The application of this method to synthetic mixture for the separation of Pd from Pt was developed.

Antibacterial and Synergistic Activity of Isocryptomerin Isolated from Selaginella tamariscina

  • Lee, June-Young;Choi, Yun-Jung;Woo, Eun-Rhan;Lee, Dong-Gun
    • Journal of Microbiology and Biotechnology
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    • 제19권2호
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    • pp.204-207
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    • 2009
  • We investigated novel antibacterial and synergistic activities of isocryptomerin isolated from Selaginella tamariscina. Isocryptomerin showed potent antibacterial activity against Gram-positive and Gram-negative bacterial strains including clinical isolates of antibiotic-resistant species such as methicillin-resistant Staphylococcus aureus(MRSA). Additionally, we further investigated the synergistic activity of isocryptomerin with a conventional antibiotic against MRSA. The result indicated that isocryptomerin had considerable synergistic activity in combination with cefotaxime. In summary, the present study suggests that isocryptomerin may have potential as a novel therapeutic agent for treatment of infectious diseases by not only human pathogenic bacteria but also multidrug-resistant bacteria.

유산균 및 효모균에 대한 화학물질의 방사선살균협력작용에 관한 연구 "D.H.A., Sorbic acid, 및 Menadion 의 협력작용에 대하여" (Studies on synergistic actions of some chemicals on radiation sterilization of Lactobacillus and yeast. "Synergistic actions of D.H.A., Sorbic acid and Menadion.")

  • 김종협;김세열
    • 미생물학회지
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    • 제5권1호
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    • pp.7-14
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    • 1967
  • The synergistic actions of certain antimetabolic agents for Saccharomyces cerevisiae and Lactobacillus plantarum on radiation sterilization have been studied. The used chemical agents are sorbic acid, vitamin-$K_3$, dehydroacetic acid, p-oxybutyl benzoate and nitrofurazone, those are the permitted as food preservatives. Experimental results are as following, 1) Survival fraction of yeast which was gamma-irradiated and influenced by sorbic acid or vitamin $K_3$ is much reduced than that of only irradiated respectively. 2) It seems like that the used chemicals acts synergistically on radiation sterilization. Sodium-dehydroacetate and p-oxybutyl benzoate are proved to be also synergistic but weakly. 3) Survival fraction of Lact. plantarum which was gamma-irradiated and influenced by sorbic acid, dehydroacetic acid or nitrofurazone respectively much reduced than that of only irradiated group, it can be estimated as synergistic action of chemical affected on radiation sterilization. 4) It was found that nutrient componets can affect radiation sterilization of microorganisms protectively.

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Synergistic Killing Effect of Synthetic Peptide P20 and Cefotaxime on Methicillin-Resistant Nosocomial Isolates of Staphylococcus aureus

  • Jung, Hyun-Jun;Choi, Kyu-Sik;Lee, Dong-Gun
    • Journal of Microbiology and Biotechnology
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    • 제15권5호
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    • pp.1039-1046
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    • 2005
  • The salt resistance of antibacterial activity and synergistic effect with clinically used antibiotic agents are critical factors in developing effective peptide antibiotic drugs. For this reason, we investigated the resistance of antibacterial activity to antagonism induced by NaCl and $MgCl_2$ and the synergistic effect of P20 with cefotaxime. P20 is a 20-residue synthetic peptide derived from a cecropin A (CA)-melittin(ME) hybrid peptide. In this study, P20 was found to have potent antibacterial activity against clinically isolated methicillin-resistant Staphylococcus aureus (MRSA) strains without hemolytic activity against human erythrocytes. The combination study revealed that P20 in combination with cefotaxime showed synergistic antibacterial activity in an energy-dependent manner. We also confirmed the synergism between P20 and cefotaxime by fluorescence-activated flow cytometric analysis by staining bacterial cells with propidium iodide (PI) and bis-(1,3-dibutylbarbituric acid) trimethine oxonol (BOX). This study suggests that P20 may be useful as a therapeutic antibiotic peptide with synergistic effect in combination with conventional antibiotic agents.

이온화 방사선 및 염화수은 처리에 따른 어류 간암세포의 생존능 평가 (Synergistic Effects of Ionizing Radiation and Mercury Chloride on Cell Viability in Fish Hepatoma Cells)

  • 한민;현경만;모하마드닐리;황인영;김진규
    • 환경생물
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    • 제27권2호
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    • pp.140-145
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    • 2009
  • All organisms are being exposed to harmful factors present in the environmental. The combined action of various factors is a distinguishing feature of modern life. An interaction between two chemicals is considered as synergistic when the effect produced is greater than the sum of the two single responses. The biological effects due to the combined action of ionizing radiation with the other factor are hard to estimate and predict in advance. In the current study, we investigated the synergistic effects between ionizing and $HgCl_2$ using fish hepatoma cells (PLHC-1 cells). The results showed a dramatic decrease of cell viability after simultaneous treatment of PLHC-1 cells with ionizing radiation and $HgCl_2$. Neiither of the two had any cytotoxic effect when treated alone. The cytotoxicity of ionizing radiation was enhanced in the presence of $HgCl_2$. The synergistic effects were observed after exposure of the PLHC-1 cells to ionizing radiation combined with $HgCl_2$. The synergistic interaction was due to an increase of irreversibly damaged cells after the combined exposure. Analysis of the extent of synergistic interaction enables to make quantitative estimation of irreversibly damaged cells after the combined exposure. The present study suggests that PLHC-1 cells can serve as rapid screening tools for detecting the toxicity of harmful factors.

Potential Complementary Knowledge, Collaborative Elaboration, and Synergistic Knowledge

  • Kim, Kyung Kyu;Shin, Ho Kyoung;Kong, Young Il
    • Asia pacific journal of information systems
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    • 제23권1호
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    • pp.107-132
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    • 2013
  • Despite the importance of knowledge complementarities (KC) to firm performance, very little is known about exactly what constitutes KC and how synergistic knowledge is created in KC. This research looks into the dimensionality of KC and how synergistic knowledge as an essential component of KC is generated in a process innovation (PI) project. We propose that KC consists of potential complementary knowledge, collaborative elaboration (CE) process, and synergistic knowledge. The model is investigated quantitatively, using a sample of 26 matched-pairs of client and consultant who participated in a PI project, and then qualitatively using interviews of a sub-sample of 7 matched-pairs of client and consultant. Data were collected in a longitudinal way at four different points during the four month project period. Results show that consultant's learning about the client's business occurs first and then client learning about IT capabilities follows through CE. With this enhanced clients' knowledge about IT capabilities, clients play an initiative role in designing the To-Be business processes, while consultants play a supporting role by introducing best practices or making suggestions based on their experiences. Future research implications as well as practical implications are also discussed.

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Machiavellianism in a Synergistic Tax Climate

  • CAHYONOWATI, Nur;RATMONO, Dwi;DEWAYANTO, Totok
    • The Journal of Asian Finance, Economics and Business
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    • 제7권12호
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    • pp.1175-1184
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    • 2020
  • This research examines the personal (i.e., Machiavellianism) and situational factors (i.e., tax climate) that are believed to be psychologically salient aspects in tax compliance. To the best of our knowledge, no research has been carried out to investigate the interaction effect of the two factors. This study uses a paper-and-pencil laboratory experiment 2x2 between-subject factorial design that involved 158 participants. The results indicate that a taxpayer who has a low Machiavellianism score or who is in a high synergistic tax climate reports a higher level of income. In the high synergistic tax climate, where tax norms apply, personal ethics do not play a significant role in tax compliance decisions. Where the synergistic relationship between taxpayer and authorities is low, personal ethics play an important role, i.e., low Machiavellians report a higher reported income than high Machiavellians do. This research contributes to the literature that deviates from the traditional model of tax compliance. Taxpayers are not always rational, but they might pay tax for reasons other than financial motives (Alm, 1991, 2018), that is, personal ethics in this study. This research implies the need for policymakers to consider other approaches rather than only relying on audits and fines.