• Communications of the Korean Mathematical Society
• /
• v.23 no.1
• /
• pp.81-93
• /
• 2008

In [3, 9], using the theory of noncommutative Dirichlet forms in the sense of Cipriani [6] and the symmetric embedding map, authors constructed the KMS-symmetric Markovian semigroup $\{S_t\}_{t{\geq}0}$ on a von Neumann algebra $\cal{M}$ with an admissible function f and an operator $x\;{\in}\;{\cal{M}}$. We give a sufficient and necessary condition for x so that the semigroup $\{S_t\}_{t{\geq}0}$ acts separately on diagonal and off-diagonal operators with respect to a basis and study some results.

• Bulletin of the Korean Chemical Society
• /
• v.18 no.7
• /
• pp.749-754
• /
• 1997

Rate constants have been measured spectrophotometrically for the reactions of alkali metal ethoxides (EtOM) with S-p-nitrophenyl 2-thiofuroate (1b) and 2-thiophenethiocarboxylate (2b) in absolute ethanol at 25.0±0.1 ℃. 1b is observed to be more reactive than 2b toward all the EtOM studied. The reactivity of EtOM is in the order EtOK > EtONa > EtO- > EtOLi for both substrates, indicating that K+ and Na+ behave as a catalyst while Li+ acts as an inhibitor in the present system. Equilibrium association constants of alkali metal ions with the transition state (KaTS) have been calculated from the known equilibrium association constants of alkali metal ion with ethoxide ion (Ka) and the rate constants for the reactions of EtOM with 1b and 2b. The catalytic effect (KaTS/Ka) is larger for the reaction of 1b than 2b, and decreases with decreasing the size of the alkali metal ions. Formation of 5-membered chelation at the transition state appears to be responsible for the catalytic effect.

• Bulletin of the Korean Chemical Society
• /
• v.17 no.11
• /
• pp.1036-1039
• /
• 1996

Synthetic lipoidal peptides based on viral protein sequences have been prepared. These peptides contain an N-palmitoyl group at the N-terminal residue, which is a modified cysteine, containing a S-[2,3-bis(acyloxy)-(2-R,S)-propyl] moiety. When this residue (Pam3Cys) is at the N-terminus of a synthetic peptide, it acts as potent immunoadjuvant to enhance both IgM and IgG antibody responses to the attached peptide. Conventional analytical procedures (e.g., Edman degradation and amino acid analysis) are either not applicable due to the N-terminal modification, or do not provide confirmation of the intact structure. Chromatographic analysis is also hindered by the tendency of these lipoidal Pam3Cys peptides to form large aggregates, and in some cases to be permanently adsorbed on reversed phase columns. We have applied several mass spectrometric techniques, including fast atom bombardment (FAB), electrospray ionization (ESI) and matrix assisted laser desorption ionization (MALDI) to characterize the intact structures of a number of different Pam3Cys synthetic peptides. The MALDI-MS has been found to be the most sensitive for the analysis of the structure of Pam3Cys peptides.

• Fisheries and Aquatic Sciences
• /
• v.22 no.5
• /
• pp.10.1-10.14
• /
• 2019

Fish skin waste accounts for part of the solid waste generated from seafood processing. Utilization of fish skin by bioconversion into high-grade products would potentially reduce pollution and economic cost associated with treating fish processing waste. Fish skin is an abundant supply of gelatin and collagen which can be hydrolyzed to produce bioactive peptides of 2-20 amino acid sequences. Bioactivity of peptides purified from fish skin includes a range of activities such as antihypertensive, anti-oxidative, antimicrobial, neuroprotection, antihyperglycemic, and anti-aging. Fish skin acts as a physical barrier and chemical barrier through antimicrobial peptide innate immune action and other functional peptides. Small peptides have been demonstrated to possess biological activities which are based on their amino acid composition and sequence. Fish skin-derived peptides contain a high content of hydrophobic amino acids which contribute to the antioxidant and angiotensin-converting enzyme inhibitory activity. The peptide-specific composition and sequence discussed in this review can be potentially utilized in the development of pharmaceutical and nutraceutical products.

• Korean Journal of Pharmacognosy
• /
• v.50 no.2
• /
• pp.118-123
• /
• 2019

Glutamate acts as an important neurotransmitter in brain. However, high concentration of glutamate showed an excitatory neurotoxicity and resulted to neuronal cell death. Neuronal cell death is known for one of the reason of Alzheimer's disease, a neurodegenerative disease. We tried to find neuroprotective medicinal plants by neuroprotection activity against glutamate injured HT22 cells as a model system. In the course of bioscreening of various medicinal plants, Taraxacum platycarpum extract showed significant neuroprotective activity. We tried to elucidate mechanisms of neuroprotective activity. T. platycarpum extract reduced ROS and intracellular $Ca^{2+}$ concentration increased by glutamate induced neurotoxicity. In addition, mitochondrial membrane potential was restored to the control level. Also, glutathione level, glutathione reductase and glutathione peroxidase activity were increased by T. platycarpum extract treatment. These data suggested that T. platycarpum showed neuroprotective activity via antioxidative activity.

• Safety and Health at Work
• /
• v.10 no.2
• /
• pp.132-140
• /
• 2019

Background: Increasing workplace health-care perception has become a major issue in the world. Most of the health-related problems are faced because of the lack of health management instruments. The level of health care can be improved through workplace health well-being regulations. The aim of the present study is to formulate a conceptual model of physical checkup. Methods: This study applied conceptual theories and figures and used secondary data from articles and relevant websites for evaluating the validity of the study. Results: Annual health checkup increases health-care awareness perception of states, organizations, employees, and their families and manages the annual health record of employees, organizations, and states. Conclusions: Health care and awareness perception of states, organizations, employees, and families improves with annual health checkup, and annual health checkup also prevents unhealthy acts.

• Biomolecules & Therapeutics
• /
• v.27 no.2
• /
• pp.145-151
• /
• 2019

Methamphetamine (METH) acts strongly on the nervous system and damages neurons and is known to cause neurodegenerative diseases such as Alzheimer's and Parkinson's. Flavonoids, polyphenolic compounds present in green tea, red wine and several fruits exhibit antioxidant properties that protect neurons from oxidative damage and promote neuronal survival. Especially, epicatechin (EC) is a powerful flavonoid with antibacterial, antiviral, antitumor and antimutagenic effects as well as antioxidant effects. We therefore investigated whether EC could prevent METH-induced neurotoxicity using HT22 hippocampal neuronal cells. EC reduced METH-induced cell death of HT22 cells. In addition, we observed that EC abrogated the activation of ERK, p38 and inhibited the expression of CHOP and DR4. EC also reduced METH-induced ROS accumulation and MMP. These results suggest that EC may protect HT22 hippocampal neurons against METH-induced cell death by reducing ER stress and mitochondrial damage.

• English & American cultural studies
• /
• v.18 no.2
• /
• pp.1-26
• /
• 2018

This paper aims to examine the performativity of street politics through Suffragette. The movie exposes the bloody violence of Britain government and shows the militant suffragettes and their resistance against it. It also deals with history and 'story'of labor class suffragettes for political rights. The paper shows how the movie is re-born as an indexical art and the street politics makes the plural performativity. Most of all, it reads the difference between the government's violence wielded as a power to suppress the suffragettes and bring them to their knees, and the suffragettes's violence having the resistant and emancipated revolution. We can realize that the suffragettes used the mode of visibility to expose its incompetence and make their emancipated violence into the indexical force. And we can see the variations of street politics from the acts of Davison, Maud, and Violet.

• International Journal of Advanced Culture Technology
• /
• v.9 no.4
• /
• pp.126-134
• /
• 2021

This study was a cross-sectional reaserch that analyzed the effect of emotional expression type on happiness level with structured questionnaires. A total of 186 participants in the study were in their 20s to 60s. Data collection was received from those who voluntarily agreed to the study from September 1 to 15, 2021. The collected data were frequency analysis, t-test, and regression analysis with spss 18.0. As a result of the analysis, it was found that people who perform superficial acts disguised as emotions were less satisfied with their current life (t=-10.482, p<0.01). People who do inner behavior showed high levels of happiness. These results suggest the following: It can be seen that in order to improve effective happiness, it is required to actively and truthfully act in a physical environment.

• The Journal of Information Systems
• /
• v.32 no.4
• /
• pp.29-50
• /
• 2023

Purpose The impact of online reviews is widely acknowledged, with extensive research focused on text-based reviews. However, there's a lack of research regarding reviews in video format. To address this gap, this study aims to explore the connection between company-sponsored product review videos and the extent of directive speech within them. This article analyzed viewer sentiments expressed in video comments based on the level of directive speech used by the presenter. Design/methodology/approach This study involved analyzing speech acts in review videos based on sponsorship and examining consumer reactions through sentiment analysis of comments. We used Speech Act theory to perform the analysis. Findings YouTubers who receive company sponsorship for review videos tend to employ more directive speech. Furthermore, this increased use of directive speech is associated with a higher occurrence of negative consumer comments. This study's outcomes are valuable for the realm of user-generated content and natural language processing, offering practical insights for YouTube marketing strategies.