• Title/Summary/Keyword: Activation product

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A Study on the Physical and Chemical Propeties of Hydrous Aluminum Oxide (합성알루마나수화물의 물리화학적 성질에 관한 연구)

  • 이계주
    • YAKHAK HOEJI
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    • v.19 no.4
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    • pp.219-226
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    • 1975
  • Physical and chemical properties on the aging inhibition mechanism of hydrous aluminum oxide were studied by means of dehydration velocity, activation energy, DTA, TGA, IR spectra, X-ray diffraction and TMA. During aging, changes may occur in the hydrous aluminum oxide structure which results in a loss of acid reactivity and in crystal formation to the hydrated hydrous alumina. The results obtained from the X-ray diffraction pattern and DTA, TGA thermogram studies showed that the aging product stabilized with either sorbitol or mannitol was hydrous aluminum oxide ($Al_{2}O_{3}{\cdot}xH_{2}O$) but the aging product not stabilized with either sorbitol or mannitol product not stabilized was hydrated hydrous aluminum oxide $Al_{2}O_{3}{\cdot}xH_{2}O{\cdot}yH_{2}O$. The activation energy of dehydration of the hydrous almina was about 17 Kcal. mol$^{1}$ deg$^{-1}$ which was observed a little less than that of 22 kcal.mol.$^{-1}$ deg.$^{-1}$ of or mannitol, the inhibition mechanism in the aging process from oxide is assumed to prevent the formation of the hydrated hydrous aluminum oxide and the aging process is thought of as analogous to the polymorphic transformations which occur as a system converts to its most stable state.

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Rate and Product Studies on the Solvolyses of Allyl Chloroformate

  • Koh, Han Joong;Kang, Suk Jin
    • Bulletin of the Korean Chemical Society
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    • v.33 no.12
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    • pp.4117-4121
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    • 2012
  • The solvolysis rate constants of allyl chloroformate ($CH_2=CHCH_2OCOCl$, 3) in 30 different solvents are well correlated with the extended Grunwald-Winstein equation, using the $N_T$ solvent nucleophilicity scale and $Y_{Cl}$ solvent ionizing scale, with the sensitivity values of $0.93{\pm}0.05$ and $0.41{\pm}0.02$ for l and m, respectively. These l and m values can be considered to support a $S_N2$ reaction pathway. The activation enthalpies (${\Delta}H^{\neq}$) were 12.5 to 13.4 $kcal{\cdot}mol^{-1}$ and the activation entropies (${\Delta}S^{\neq}$) were -34.4 to -37.3 $cal{\cdot}mol^{-1}{\cdot}K^{-1}$, which is also consistent with the proposed bimolecular reaction mechanism. The solvent kinetic isotope effect (SKIE, $k_{MeOH}/k_{MeOD}$) of 2.16 was also in accord with the $S_N2$ mechanism. The values of product selectivity (S) for the solvolyses of 3 in alcohol/water mixtures was 1.3 to 3.9, which is also consistent with the proposed bimolecular reaction mechanism.

A study of the traditional graphic patterns between Chinese and korea - Based on the periods of the joseon Dynasty period and the Ming Dynasty - (한국과 중국 전통 문양 비교 연구 - 조선시대와 명나라 시대 가구를 중심으로 -)

  • Lixuejing, Lixuejing;Song, Man-Yong;Lee, Chang-Gun
    • Proceedings of the Korea Contents Association Conference
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    • 2008.05a
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    • pp.708-711
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    • 2008
  • Through the analysis and the caomparation of the furture patterns between the China Ming dynasty and the Korea joseon dynasty, we try to searches for the culturl value of the appreciation possibility to the concept design by the aesthetic and objective tools in this paper. For making cultural and economic mind. cultural product as well-mated as 21st century is how traditional pattern might design, but how fassionable design in modern is attracted. As making and providing those mind, it is observed what the strategy of program activation could be. it is to be desired that is provided the use of product as traditional pattern of today on the traditional pattern of today based on the mentioned above. Hence, it is looked to activation in the modern pattern for development of cultural product.

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Effects of Curcumin, the Active Ingredient of Turmeric(Curcuma longa), on Regulation of Glutamate-induced Toxicity and Activation of the Mitogen-activated Protein Kinase Phosphatase-1 (MKP-1) in HT22 Neuronal Cell

  • Lee, Sang-Hyun;Yun, Young-Gab
    • Natural Product Sciences
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    • v.15 no.1
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    • pp.32-36
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    • 2009
  • Glutamate causes neurotoxicity through formation of reactive oxygen species and activation of mitogen-activated protein kinase (MAPK) pathways. MAPK phosphatase-1 (MKP-1) is one of the phosphatases responsible for dephosphorylation/deactivation of three MAPK families: the extracellular signal-regulated kinase-1/2 (ERK-1/2), the c-Jun N-terminal kinase-1/2 (JNK-1/2), and the p38 MAPK. In this report, the potential involvement of MKP-1 in neuroprotective effects of curcumin, the active ingredient of turmeric (Curcuma longa), was examined using HT22 cells. Glutamate caused cell death and activation of ERK-1/2 but not p38 MAPK or JNK-1/2. Blockage of ERK-1/2 by its inhibitor protected HT22 cells against glutamate-induced toxicity. Curcumin attenuated glutamate-induced cell death and ERK-1/2 activation. Interestingly, curcumin induced MKP-1 activation. In HT22 cells transiently transfected with small interfering RNA against MKP-1, curcumin failed to inhibit glutamate-induced ERK-1/2 activation and to protect HT22 cells from glutamate-induced toxicity. These results suggest that curcumin can attenuate glutamate-induced neurotoxicity by activating MKP-1 which acts as the negative regulator of ERK-1/2. This novel pathway may contribute to and explain at least one of the neuroprotective actions of curcumin.

BSCCO Superconducting Powder by SHS

  • Soh, Dea-Wha;Cho, Yong-Joon;Korobova, N.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.11a
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    • pp.99-102
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    • 2002
  • The BSCCO superconductor materials of using Self-propagating High-temperature Synthesis (SHS) were studied. Mechano-chemical activation - as a pre-treatment of the reactants mixture - strongly influences the kinetic parameters, the reaction mechanism, and the composition and structure of the final product. In this paper as an effort for fabricating the SHSed BSCCO superconductor powder SHS method was considered to application in the synthesis of superconducting materials.

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Neuroprotective Effect of Astersaponin I against Parkinson's Disease through Autophagy Induction

  • Zhang, Lijun;Park, Jeoung Yun;Zhao, Dong;Kwon, Hak Cheol;Yang, Hyun Ok
    • Biomolecules & Therapeutics
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    • v.29 no.6
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    • pp.615-629
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    • 2021
  • An active compound, triterpene saponin, astersaponin I (AKNS-2) was isolated from Aster koraiensis Nakai (AKNS) and the autophagy activation and neuroprotective effect was investigated on in vitro and in vivo Parkinson's disease (PD) models. The autophagy-regulating effect of AKNS-2 was monitored by analyzing the expression of autophagy-related protein markers in SH-SY5Y cells using Western blot and fluorescent protein quenching assays. The neuroprotection of AKNS-2 was tested by using a 1-methyl-4-phenyl-2,3-dihydropyridium ion (MPP+)-induced in vitro PD model in SH-SY5Y cells and an MPTP-induced in vivo PD model in mice. The compound-treated SH-SY5Y cells not only showed enhanced microtubule-associated protein 1A/1B-light chain 3-II (LC3-II) and decreased sequestosome 1 (p62) expression but also showed increased phosphorylated extracellular signal-regulated kinases (p-Erk), phosphorylated AMP-activated protein kinase (p-AMPK) and phosphorylated unc-51-like kinase (p-ULK) and decreased phosphorylated mammalian target of rapamycin (p-mTOR) expression. AKNS-2-activated autophagy could be inhibited by the Erk inhibitor U0126 and by AMPK siRNA. In the MPP+-induced in vitro PD model, AKNS-2 reversed the reduced cell viability and tyrosine hydroxylase (TH) levels and reduced the induced α-synuclein level. In an MPTP-induced in vivo PD model, AKNS-2 improved mice behavioral performance, and it restored dopamine synthesis and TH and α-synuclein expression in mouse brain tissues. Consistently, AKNS-2 also modulated the expressions of autophagy related markers in mouse brain tissue. Thus, AKNS-2 upregulates autophagy by activating the Erk/mTOR and AMPK/mTOR pathways. AKNS-2 exerts its neuroprotective effect through autophagy activation and may serve as a potential candidate for PD therapy.

Neuro-scientific Approach to Fashion Visual Merchandising -Comparison of Brain Activation to Positive/Negative VM in Fashion Store Using fNIRS- (패션 비주얼머천다이징의 뇌 과학적 접근 -fNIRS를 이용한 패션매장의 긍정적/부정적 VM에 대한 뇌 활성 비교-)

  • Kim, Hyoung Suk;Lee, Jin Hwa
    • Journal of the Korean Society of Clothing and Textiles
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    • v.41 no.2
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    • pp.254-265
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    • 2017
  • This study examines the possibility of a neuro-scientific approach to fashion Visual Merchandising (VM), by researching the brain activation of customers about fashion stores in terms of VM. Study subjects were in 20's-30's residing in Busan and ten ordinary person or fashion industry related individuals, it measures the change of cerebral blood flow on positive/negative photo stimulus in terms of VM using a functional Near Infrared Spectroscopy (fNIRS) device, and then compared the brain activation to the difference of the fashion store VM. Photo stimuli utilized in the experiment were selected through a preliminary study in advance. The results of this study are as follows. First, the brain activation was found in all 16 channels of stimulus ranges of fashion store VM regardless of positive/negative stimulus. This means that the VM of fashion store causes changes to the cerebral blood flow of consumers, which implies that consumer behavior can be affected by store VM. It also shows that the brain is more active in negative VM stimulus than positive VM despite slight differences in the subjects. In terms of VM, this suggests that the negative factors of fashion stores have a greater effect on the brains of consumers compared to the positive factors. Second, the reaction of the brain channel is different according to the positive/negative VM stimulus of the fashion store by product group and confirms that positive/negative VM stimulus can be distinguished by brain-reaction for the three product groups except for the underwear group among four product groups (men's wear store, women's wear store, underwear store, and sportswear store). The results indicate that more objective scientific measure and decision-making are possible through neuro-science in the strategic execution of VM. This study verified the possibility for a neuro-scientific approach to fashion VM; therefore, there are expectations for the various activation of interdisciplinary research and subsequent development of VM that utilize neuroscience in fashion marketing.

Role of Acyl-CoA Synthetase 4, an Arachidonate-Preferring Enzyme Expressed in Steroidogenic Tissues

  • Kang, M.J.
    • Korean Journal of Animal Reproduction
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    • v.24 no.4
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    • pp.339-341
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    • 2000
  • In mammals, fatty acid utilization is initiated by activation of fatty acid, catalyzed by acyl-CoA synthetase(ACS, EC6.2.1.3). This enzyme reaction is essential in fatty acid metabolism, since mammalian fatty acid synthetase contains a specific thioesterase to produce fatty acid as th $\varepsilon$ final reaction product. Acyl-CoA, the product of ACS, is utilized in various metabolic pathways including membrane biogenesis, energy production and fat deposition. (omitted)

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