• Title/Summary/Keyword: blocking effects

Search Result 653, Processing Time 0.025 seconds

Factors Impacting Public Technology Transfer and Commercialization and Its Strategy for R&D Management (공공기술이전·사업화 영향요인 및 연구개발 관리전략)

  • Sung, Oong-Hyun;Moon, Hye-Jung;Kang, Hun
    • Journal of Korea Technology Innovation Society
    • /
    • v.18 no.3
    • /
    • pp.468-491
    • /
    • 2015
  • The major objective of this research is to suggest the proactive strategy and management of public R&D for the active transfer of technology based on the influential factor analysis of technology transfer. This study identified influential factors which make the greatest impact on the success of public technology transfer and commercialization through three points of view-technology supplier's view, technology adopter's view and view of commercialization-which contribute to successful technology transfer and commercialization. The core influential variables for blocking technology transfer are identified such as additional technological development, search for technology adopter followed by mass production technology and testing of confidence. Technology adopter is to create new markets or expand existing markets through the superiority (innovation) of licensing technology, increasing the internal innovation capabilities and maximizing the impacts of technology. This research suggests two effective strategies for improving technology transfer such as technology planning and marketing in the view of technology license. The strategy of technology planning should be established and executed to meet both technology trends and adopter's needs. And strong patents should be secured in terms of licensing of technology. Also the technological performance should be evaluated at mid-term appraisal, confirming the needs of adopter and competitive advantage of technology and patent. In addition to this, the customized technology marketing strategy for different fields of applications is also required in order to improve the likelihood of technology transfer. If the performance of R&D organization could be evaluated by global technological competitiveness and spillover effects of commercialization rather than quantitative output, the flow of technology transfer and commercialization would be accelerated.

Multiple Residues in the P-Region and M2 of Murine Kir 2.1 Regulate Blockage by External $Ba^{2+}$

  • Lee, Young-Mee;Thompson, Gareth A.;Ashmole, Ian;Leyland, Mark;So, In-Suk;Stanfield, Peter R.
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.13 no.1
    • /
    • pp.61-70
    • /
    • 2009
  • We have examined the effects of certain mutations of the selectivity filter and of the membrane helix M2 on $Ba^{2+}$ blockage of the inward rectifier potassium channel, Kir 2.1. We expressed mutant and wild type murine Kir 2.1 in Chinese hamster ovary(CHO) cells and used the whole cell patch-clamp technique to record $K^+$ currents in the absence and presence of externally applied $Ba^{2+}$. Wild type Kir2.1 was blocked by externally applied $Ba^{2+}$ in a voltage and concentration dependent manner. Mutants of Y145 in the selectivity filter showed little change in the kinetics of $Ba^{2+}$ blockage. The estimated $K_d(0)$ was 108 ${\mu}M$ for Kir2.1 wild type, 124 ${\mu}M$ for a concatameric WT-Y145V dimer, 109 ${\mu}M$ for a WT-Y145L dimer, and 267 ${\mu}M$ for Y145F. Mutant channels T141A and S165L exhibit a reduced affinity together with a large reduction in the rate of blockage. In S165L, blockage proceeds with a double exponential time course, suggestive of more than one blocking site. The double mutation T141A/S165L dramatically reduced affinity for $Ba^{2+}$, also showing two components with very different time courses. Mutants D172K and D172R(lining the central, aqueous cavity of the channel) showed both a decreased affinity to $Ba^{2+}$ and a decrease in the on transition rate constant(${\kappa}_{on}$). These results imply that residues stabilising the cytoplasmic end of the selectivity filter(T141, S165) and in the central cavity(D172) are major determinants of high affinity $Ba^{2+}$ blockage in Kir 2.1.

Pre-service Chemistry Teachers’ Understanding of the Boiling Process of a Liquid Mixture (액체 혼합물의 끓음에 대한 예비 화학교사의 이해)

  • Park, Kira;Yoon, Heesook
    • Journal of the Korean Chemical Society
    • /
    • v.59 no.5
    • /
    • pp.454-465
    • /
    • 2015
  • The goal of this study is to investigate pre-service chemistry teachers’ understanding of the boiling process of a liquid mixture. We surveyed 65 students in the chemistry program of the College of Education about the boiling point of a 50%(by mole) ethanol aqueous solution and the temperature changes during heating. We then interviewed 9 of these students. According to the survey results, the percent of the pre-service teachers who thought that the boiling point of the ethanol solution would be ‘between the boiling points of ethanol and water (78-100 ℃)’ and ‘the same as that of ethanol’ were 52.3% and 35.4%, respectively. The majority of those who stated the former explained that the boiling point of the ethanol solution increased due to the effects of attraction or blocking by water molecules. Most of those who believed the latter explained that physical properties such as the boiling point would not be changed by the addition of water. With regard to the temperature change during heating, 69.2% of the teachers thought that the temperature would increase gradually while boiling, which some thought resulted from the increasing amount of water in the solution as the ethanol boiled off. Others thought that two temperature plateaus would be observed as each component of the liquid mixture underwent phase transition at its specific boiling point. When asked about the particle model of the gas phase during the boiling and evaporation process, some students drew both ethanol and water during evaporation but only ethanol when boiling. We discussed several alternative concepts of pre-service chemistry teachers about the boiling process of liquid mixtures and ways to improve their understanding.

A Study on the Improvement of Digital Periapical Images using Image Interpolation Methods (영상보간법을 이용한 디지털 치근단 방사선영상의 개선에 관한 연구)

  • Song Nam-Kyu;Koh Kawng-Joon
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
    • /
    • v.28 no.2
    • /
    • pp.387-413
    • /
    • 1998
  • Image resampling is of particular interest in digital radiology. When resampling an image to a new set of coordinate, there appears blocking artifacts and image changes. To enhance image quality, interpolation algorithms have been used. Resampling is used to increase the number of points in an image to improve its appearance for display. The process of interpolation is fitting a continuous function to the discrete points in the digital image. The purpose of this study was to determine the effects of the seven interpolation functions when image resampling in digital periapical images. The images were obtained by Digora, CDR and scanning of Ektaspeed plus periapical radiograms on the dry skull and human subject. The subjects were exposed to intraoral X-ray machine at 60kVp and 70 kVp with exposure time varying between 0.01 and 0.50 second. To determine which interpolation method would provide the better image, seven functions were compared; (1) nearest neighbor (2) linear (3) non-linear (4) facet model (5) cubic convolution (6) cubic spline (7) gray segment expansion. And resampled images were compared in terms of SNR(Signal to Noise Ratio) and MTF(Modulation Transfer Function) coefficient value. The obtained results were as follows ; 1. The highest SNR value(75.96dB) was obtained with cubic convolution method and the lowest SNR value(72.44dB) was obtained with facet model method among seven interpolation methods. 2. There were significant differences of SNR values among CDR, Digora and film scan(P<0.05). 3. There were significant differences of SNR values between 60kVp and 70kVp in seven interpolation methods. There were significant differences of SNR values between facet model method and those of the other methods at 60kVp(P<0.05), but there were not significant differences of SNR values among seven interpolation methods at 70kVp(P>0.05). 4. There were significant differences of MTF coefficient values between linear interpolation method and the other six interpolation methods (P< 0.05). 5. The speed of computation time was the fastest with nearest -neighbor method and the slowest with non-linear method. 6. The better image was obtained with cubic convolution, cubic spline and gray segment method in ROC analysis. 7. The better sharpness of edge was obtained with gray segment expansion method among seven interpolation methods.

  • PDF

Transduced Tat-Annexin protein suppresses inflammation-associated gene expression in lipopolysaccharide (LPS)-stimulated Raw 264.7 cells

  • Lee, Sun-Hwa;Kim, Dae-Won;Back, Su-Sun;Hwang, Hyun-Sook;Park, Eun-Young;Kang, Tae-Cheon;Kwon, Oh-Shin;Park, Jong-Hoon;Cho, Sung-Woo;Han, Kyu-Hyung;Park, Jin-Seu;Eum, Won-Sik;Choi, Soo-Young
    • BMB Reports
    • /
    • v.44 no.7
    • /
    • pp.484-489
    • /
    • 2011
  • Annexin-1 (ANX1) is an anti-inflammatory protein as well as an important modulator in inflammation. However, the precise action of ANX1 remains unclear. To elucidate the protective effects of ANX1 on lipopolysaccharide (LPS)-induced murine macrophage Raw 264.7 cells, we constructed a cell-permeable Tat-ANX1 protein. The transduced Tat-ANX1 protein markedly inhibited the expression of cyclooxygenase-2, production of prostaglandin $E_2$, and generation of pro-inflammatory cytokines in the cells. Furthermore, transduced Tat-ANX1 protein caused a significant reduction in the activation of nuclear factor-kappa B (NF-${\kappa}B$) and mitogen-activated protein kinase (MAPK). The results indicate that Tat-ANX1 inhibits the production of inflammatory response cytokines and enzymes by blocking NF-${\kappa}B$ and MAPK. Therefore, Tat-ANX1 protein may be useful as a therapeutic agent against various inflammatory diseases.

Anti-Inflammatory Effect of Ixeris dentata on Ultraviolet B-Induced HaCaT Keratinocytes

  • Kim, Sung-Bae;Kang, Ok-Hwa;Keum, Joon-Ho;Mun, Su-Hyun;An, Hyun-Jin;Jung, Hyun-Ju;Hong, Seung-Heon;Jeong, Dong-Myong;Kweon, Kee-Tae;Kwon, Dong-Yeul
    • Natural Product Sciences
    • /
    • v.18 no.1
    • /
    • pp.60-66
    • /
    • 2012
  • Human skin is the first line of defense for the protection of the internal organs of the body from different stimuli. Ultraviolet B (UVB) irradiation induces skin damage and inflammation through the secretion of various cytokines, which are immune regulators produced by cells. To prevent the initiation of skin inflammation, keratinocytes that have been irreversibly damaged by radiation must be removed through the apoptotic mechanism. Ixeris dentata (family: Asteraceae) is a perennial medicinal herb indigenous to Korea. It has been used in Korea, China, and Japan to treat in digestion, pneumonia, diabetes, hepatitis, and tumors. To gain insight into the anti-inflammatory effects of I. dentata, we examined its influence on UVB-induced pro-inflammatory cytokine production in human keratinocytes (HaCaT cells), by observing cells that were stimulated with UVB in the presence or absence of I. dentata. In the present study, pro-inflammatory cytokine production was determined by performing enzyme-linked immunosorbent assay, reverse transcription polymerase chain reaction, and western blot analysis to measure the activation of mitogen-activated protein kinase (MAPKs). I. dentata inhibited UVBinduced production of the pro-inflammatory cytokine interleukin (IL)-6 in a dose-dependent manner. Further, I. dentata inhibited the UVB-induced expression of cyclooxygenase (COX)-2. Furthermore, I. dentata inhibited the phosphorylation of c-Jun NH2-terminal kinase and p38 MAPKs, suggesting that it inhibits the secretion of the pro-inflammatory cytokines IL-6 and IL-8, and COX-2 expression, by blocking MAPK phosphorylation. These results suggest that I. dentate can potentially protect against UVB-induced skin inflammation.

Performance Improvement of Single Chip Multiprocessor using Concurrent Branch Execution (분기 동시 수행을 이용한 단일 칩 멀티프로세서의 성능 개선)

  • Lee, Seung-Ryul;Kim, Jun-Shik;Choi, Jae-Hyeok;Choi, Sang-Bang
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.44 no.2
    • /
    • pp.61-71
    • /
    • 2007
  • The instruction level parallelism, which has been used to improve the performance of processors, expose its limit. The change of a control flow by a branch miss prediction is one of the obstacles that restrict the instruction level parallelism. The single chip multiprocessors have been developed to utilize the thread level parallelism. However, we could not use the maximum performance of the single chip multiprocessor in case of executing the coded programs without considering the multi-thread. In order to overcome the two performance degradation factors, in this paper, we suggest the concurrent branch execution method that applies to the multi-path execution method at a single chip multiprocessor. We executes all two flows of the conditional branch using the idle core processor. Through this, we can improve the processor's efficiency with blocking the control flow termination by the branch instruction and reducing the idle time. We analyze the effects of concurrent branch execution proposed in this paper through the simulation. As a result of that, concurrent branch execution reduces about 20% of idle time and improves the maximum 10% of the branch prediction accuracy. We show that our scheme improves the overall performance of maximum 39% compared to the normal single chip multiprocessor and maximum 27% compared to the superscalar processor.

Protective Effects of 2-(Allylthio)pyrazine on Retinoyl Palmitate- and Pyridine-Potentiated Carbon tetrachloride- induced Hepatotoxicity: Effect on ${\Phi}x$-174 DNA Strand Breakage (비타민 A 및 피리딘으로 유발된 사염화탄소 유발성 간독성에 대한 2-(알릴티오)피라진의 보호효과: ${\Phi}$x-174 DNA 손상에 미치는 효과)

  • Kim, Sang-Geon;Cho, Joo-Youn;Choi, Sung-Hee;Kim, Nak-Doo
    • YAKHAK HOEJI
    • /
    • v.40 no.6
    • /
    • pp.727-733
    • /
    • 1996
  • 2-(Allylthio)pyrazine is effective in selectively suppressing constitutive and inducible expression of cytochrome P450 2E1. The effect of 2-(allylthio)pyrazine against potentiat ed chemical injury was studied in rats. Vitamin-A pretreatment of rats substantially increased carbon tetrachloride hepatotoxicity, as supported by an ~4-fold increase in serum alanine aminotransferase (ALT) activity. Concomitant pretreatment of rats with 2-(allylthio)pyrazine at the daily dose of 200mg/kg resulted in a 76% decrease in vitamin-A-potentiated hepatotoxicity, which supported the possibility that 2-(allylthio)pyrazine protects the liver against chemical-induced hepatic injury by the mechanism associated with Kupffer cell inactivation. Pyridine pretreatment caused substantial enhancement in carbon tetrachloride hepatotoxicity. 2-(Allylthio)pyrazine treatment of rats reduced the pyridine-potentiated toxicity in a dose-dependent manner. Animals treated with both pyridine and 2-(allylthio)pyrazine prior to intoxicating dose of CCl$_4$ resulted in 85% and 47% decreases in pyridine-increased triglycerides and cholesterol levels in the liver. The protective effect of 2-(allylthio)pyrazine on the DNA strand breakage induced by benzenetriol was assessed by measuring the conversion of supercoiled ${\Phi}x$-174 DNA to the open relaxed form. 2-(Allylthio)pyrazine blocked the benzenetriol-induced conversion of supercoiled DNA to open circular form in a dose-dependent manner. The presence of 2-(allylthio)pyrazine at the doses from I to 10mM in the incubation mixture containing 5 ${\mu}$M benzenetriol completely protected benzenetriol-induced DNA strand breakage with the EC50 for the 2-(allylthio)pyrazine blocking being noted as ~220 ${\mu}$M, whereas allyl disulfide exerted protecting effect at relatively high concentrations (i.e. ~850 ${\mu}$M), suggesting that 2-(allylthio)pyrazine effectively scavenges the reactive oxygen species. These results provide evidence that 2-(allylthio)pyrazine blocks vitamin A- or pyridine-potentiated CCl$_4$ hepatotoxicity and that the agent is active in protecting DNA by scavenging the reactive oxygen species.

  • PDF

Beneficial effects of fermented black ginseng and its ginsenoside 20(S)-Rg3 against cisplatin-induced nephrotoxicity in LLC-PK1 cells

  • Han, Myoung-Sik;Han, Im-Ho;Lee, Dahae;An, Jun Min;Kim, Su-Nam;Shin, Myoung-Sook;Yamabe, Noriko;Hwang, Gwi Seo;Yoo, Hye Hyun;Choi, Suk-Jung;Kang, Ki Sung;Jang, Hyuk-Jai
    • Journal of Ginseng Research
    • /
    • v.40 no.2
    • /
    • pp.135-140
    • /
    • 2016
  • Background: Nephrotoxicity is a common side effect of medications. Panax ginseng is one of the best-known herbal medicines, and its individual constituents enhance renal function. Identification of its efficacy and mechanisms of action against drug-induced nephrotoxicity, as well as the specific constituents mediating this effect, have recently emerged as an interesting research area focusing on the kidney protective efficacy of P. ginseng. Methods: The present study investigated the kidney protective effect of fermented black ginseng (FBG) and its active component ginsenoside 20(S)-Rg3 against cisplatin (chemotherapy drug)-induced damage in pig kidney (LLC-PK1) cells. It focused on assessing the role of mitogen-activated protein kinases as important mechanistic elements in kidney protection. Results: The reduced cell viability induced by cisplatin was significantly recovered with FBG extract and ginsenoside 20(S)-Rg3 dose-dependently. The cisplatin-induced elevated protein levels of phosphorylated c-Jun N-terminal kinase (JNK), p53, and cleaved caspase-3 were decreased after cotreatment with FBG extract or ginsenoside 20(S)-Rg3. The elevated percentage of apoptotic LLC-PK1 cells induced by cisplatin treatment was significantly abrogated by cotreatment with FBG and the ginsenoside 20(S)-Rg3. Conclusion: FBG and its major ginsenoside 20(S)-Rg3, ameliorated cisplatin-induced nephrotoxicity in LLC-PK1 cells by blocking the JNKep53ecaspase-3 signaling cascade.

Geochronology and Cooling history of the Mesozoic Granite Plutons in the Central Part of the Ogcheon Fold Belt, South Korea (남한 습곡대 중앙부의 중생대 화강암 질암의 생선년대와 냉각사)

  • Myung-Shik JIN
    • The Journal of the Petrological Society of Korea
    • /
    • v.4 no.2
    • /
    • pp.153-167
    • /
    • 1995
  • Emplacement ages for the granite plutons of the Jurassic and the Cretaceous times in the central Ogcheom Fold Belt were determined by Rb-Sr whole rock and mineral isocheon methods. In addition mineral ages for the plutons were determined by K-Ar and fission track methods. In turn, thermal histories and uplifting rates of the granitic bodies are elucidated from the isotopic ages. The Jecheon(~203 Ma) and Mungyeong(at lest~200 Ma) granites of the Jurassic and the Muamsa, Wolagsan and Daeyasan granites(~110 Ma) of the Cretaceous show high strontium initial ratios [$(^{87}Sr/^{86}Sr)_1$0.7100],suggesting that the granitic magmas have been generated by partial melting of crustal materials (S-type), or by mixing of mantle and crustal materials. Only mineral ages of the Sogrisan and Hyeongjebong granites (~90 Ma) were determined by K-Ar method, and petrogenesis of them were not defined yet. The two Jurassic granite plutons were cooled rapidly down to $300^{\circ}C$, right after the plutons were slowly cooled down since then, due to their deep emplacment. During the Middle Cretaceous period, the Jurassic Mungyeong granitic pluton was intruded and thermally affected much by the surrounding Wolagsan and Daeyasan granites. Accordingly the Rb-Sr mineral age, K-Ar hornblende and biotite ages of the Mungyeong granite appear to be reduced or reset due to the thermal effects above their blocking temperatures. All the cretaceous granites have been cooled much ore simply and rapidly down than the Jurassic ones below $300^{\circ}C$, owing to their shallow emplacement.

  • PDF