• Journal of Korea Multimedia Society
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• v.7 no.12
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• pp.1754-1764
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• 2004

Lately mobile handheld devices such as Personal Digital Assistant (PDA) and cellular phones are getting more popular for personal web surfing. However, today most mobile handheld devices have relatively poor web browsing capability due to their low performance so their users have to suffer longer communication latency than those of desktop Personal Computers (PCs). In this paper, we propose an effective pre-refresh mechanism for embedded web browser of mobile handheld devices to reduce this problem. The proposed mechanism uses the idle time to pre-refresh the expired web objects in an embedded web browser's cache memory. It increases the utilization of Central Processing Unit (CPU) power and network bandwidth during the idle time and consequently reduces the client's latency and web browsing cost. An experiment was done using a simulator designed by us to evaluate the efficacy of the proposed mechanism. The experiment result demonstrates that it has a good performance to make web surfing faster.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.189.2-190
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• 2003

Methylmercury (MeHg), one of the heavy metal compounds. can cause severe damage to the central nervous system in humans. Many reports have shown that MeHg is poisonous to human body through contaminated foods and has released into the environment. Despite many studies on the pathogenesis of MeHg-induced central neuropathy, no useful mechanism of toxicity has been established so far. (omitted)

• Proceedings of the Safety Management and Science Conference
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• 2009.04a
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• pp.423-427
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• 2009

This study proposes the generation mechanism of various design matrix using generalized linear model for design of experiment. Design generation method of GLM analysis, factorial design(FD) with center points, ANOVA design with lack-of-fit test, and response surface design are introduced. In central composite(CC) design, orthogonal blocking and fractional factorial design(FFD) are presented. We compare the design of Box-Benhken(BB) and face-centred central compsite design.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.11b
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• pp.153-153
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• 2002

Methylmercury (MeHg), one of the heavy metal compound, can cause severe damage to the central nervous system in humans. Many reports have contributed MeHg poisoning to contaminated foods and release into the environment. Despite many studies on the pathogenesis of MeHg-induced central neuropathy, no useful mechanism of toxicity has been established.(omitted)

• Archives of Pharmacal Research
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• v.27 no.4
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• pp.436-441
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• 2004

SJ compounds (SJ8002 and related compounds) are a group of novel anticancer agents (Cho, Chung, Lee, Kwon, Kang, Joo, and Oh. PCT/KR02/00392). To explore the anticancer mechanism of these compounds, we examined the effect of SJ8002 on microtubules of six human cell lines. At a high concentration ($2\;{\mu}g/mL$), SJ8002 effectively disrupted microtubules of the six cell lines within 1 h. At lower concentrations ($0.05\~1.0\;{\mu}g/mL$), the antimicrotubule activity of SJ8002 varied defending on cell lines. The inhibition of in vitro polymerization of pure tubulin by SJ8002 suggested that SJ8002 acts on free tubulin, inhibits the polymerization of tubulin dimer into microtubules, and hence induces the depolymerization of microtubules.

• Wind and Structures
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• v.26 no.5
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• pp.305-315
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• 2018

A numerical study based on a delayed detached eddy simulation (DDES) is conducted to investigate the aerodynamic mechanism behind the suppression of vortex-induced vibrations (VIVs) of twin box girders by central grids, which have an inhibition effect on VIVs, as evidenced by the results of section model wind tunnel tests. The mean aerodynamic force coefficients with different attack angles are compared with experimental results to validate the numerical method. Next, the flow structures around the deck and the aerodynamic forces on the deck are analyzed to enhance the understanding of the occurrence of VIVs and the suppression of VIVs by the application of central grids. The results show that shear layers are separated from the upper railings and lower overhaul track of the upstream girder and induce large-scale vortices in the gap that cause periodical lift forces of large amplitude acting on the downstream girder, resulting in VIVs of the bridge deck. However, the VIVs are apparently suppressed by the central grids because the vortices in the central gap are reduced into smaller vortices and become weaker, causing slightly fluctuating lift forces on the deck. In addition, the mean lift force on the deck is mainly caused by the upstream girder, whereas the fluctuating lift force is mainly caused by the downstream girder.

• The Korean Journal of Pain
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• v.37 no.2
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• pp.107-118
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• 2024

Nociplastic pain by the "International Association for the Study of Pain" is defined as pain that arises from altered nociception despite no clear evidence of nociceptive or neuropathic pain. Augmented central nervous system pain and sensory processing with altered pain modulation are suggested to be the mechanism of nociplastic pain. Clinical criteria for possible nociplastic pain affecting somatic structures include chronic regional pain and evoked pain hypersensitivity including allodynia with after-sensation. In addition to possible nociplastic pain, clinical criteria for probable nociplastic pain are pain hypersensitivity in the region of pain to non-noxious stimuli and presence of comorbidity such as generalized symptoms with sleep disturbance, fatigue, or cognitive problems with hypersensitivity of special senses. Criteria for definitive nociplastic pain is not determined yet. Eight specific disorders related to central sensitization are suggested to be restless leg syndrome, chronic fatigue syndrome, fibromyalgia, temporomandibular disorder, migraine or tension headache, irritable bowel syndrome, multiple chemical sensitivities, and whiplash injury; non-specific emotional disorders related to central sensitization include anxiety or panic attack and depression. These central sensitization pain syndromes are overlapped to previous functional pain syndromes which are unlike organic pain syndromes and have emotional components. Therefore, nociplastic pain can be understood as chronic altered nociception related to central sensitization including both sensory components with nociceptive and/or neuropathic pain and emotional components. Nociplastic pain may be developed to explain unexplained chronic pain beyond tissue damage or pathology regardless of its origin from nociceptive, neuropathic, emotional, or mixed pain components.

• Journal of Microbiology and Biotechnology
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• v.11 no.4
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• pp.619-627
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• 2001

n order to increase the virus safety of a human intravenous immunoglobulin (IVIg) that was manufactured by a successive process of cold ethanol fractionation, polyethylene glycol precipitation, and pasteurization ($60^{\circ}C$ heat treatment for 10h), a low pH incubation process (pH 3.9 at $25{\circ}C$ for 14 days) was employed as the final step. The efficacy and mechanism of the fraction III cold ethanol fractionation, pasteurization, and low pH treatment steps in the removal and/or inactivation of blood-borne viruses were closely examined. A variety of experimental model viruses for human pathogenic viruses, including the Bovine herpes virus (BHV), Bovine viral diarrhoea virus (BVDV), Murine encephalomyocarditis virus (EMCV), and Porcine parvovirus (PPV), were selected for this study. The mechanism of reduction for the enveloped viruses (BHV and BVDV) during fraction III fractionation was both inactivation and partitioning, however, it was partitioning in the case of the nonenveloped viruses (EMCV and PPV). The log reduction factors achieved during fraction III fractionation were ${\geqq}$6.7 for BHV, ${\geqq}4.7$ for BVDV, 4.5 for EMCV, and 4.4 for PPV. Pasteurization was found to be a robust and effective step in inactivating all the viruses tested. The log reduction factors achieved during the pasteurization process were ${\geqq}7.5$ for BHV, ${\geqq}4.8$ for BVDV, 3.0 for EMCV, and 3.3 for PPV. A low pH incubation was very effective in inactivating the enveloped viruses as well as EMCV. The log reduction factors achieved during low pH incubation were ${\geqq}7.4$ for BHV, ${\geqq}3.9$ for BVDV, 5.2 for EMCV, and 2.0 for PPV. These results indicate that the low pH treatment successfully improved the viral safety of the final products.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.5825-5831
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• 2013

Background/Objectives: Maintenance of cellular function in culture is vital for transfer and development following adoptive immunotherapy. Dual properties of IL-21 in activating T cells and reducing activation induced cell death led us to explore the mechanism of action of IL-21 enhanced proliferation and cytotoxic potential of CIK cells. Method: CIK cells cultured from PBMCs of healthy subjects were stimulated with IL-21 and cellular viability and cytotoxicity to K562 cells were measured. To elucidate the mechanism of action of IL-21, mRNA expression of cytotoxic factors was assessed by RT-PCR and protein expression of significantly important cytotoxic factors and cytokine secretion were determined through flow cytometry and ELISA. Western blotting was performed to check the involvement of the JAK/STAT pathway following stimulation. Results: We found that IL-21 did not enhance in vitro proliferation of CIK cells, but did increase the number of cells expressing the CD3+/CD56+ phenotype. Cytotoxic potential was increased with corresponding increase in perforin ($0.9831{\pm}0.1265$ to $0.7592{\pm}0.1457$), granzyme B ($0.4084{\pm}0.1589$ to $0.7319{\pm}0.1639$) and FasL ($0.4015{\pm}0.2842$ to $0.7381{\pm}0.2568$). Interferon gamma and TNF-alpha were noted to increase ($25.8{\pm}6.1ng/L$ to $56.0{\pm}2.3ng/L$; and $5.64{\pm}0.61{\mu}g/L$ to $15.14{\pm}0.93{\mu}g/L$, respectively) while no significant differences were observed in the expression of granzyme A, TNF-alpha and NKG2D, and NKG2D. We further affirmed that IL-21 signals through the STAT-3 and STAT-5b signaling pathway in the CIK cell pool. Conclusion: IL-21 enhances cytotoxic potential of CIK cells through increasing expression of perforin, granzyme B, IFN-gamma and TNF-alpha. The effect is brought about by the activation of STAT-3 and STAT-5b proteins.

• Journal of the Korean Society of Safety
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• v.10 no.3
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• pp.42-46
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• 1995

To purpose of this study is to model design and motion analysis of tangential cam mechanism using personal computer system. The CAD(Computer Aided Design) system used in this study was constructed with CPU(Central Processing Unit) 80486, RAM(Random Access Memory) 8M, CGA graphic card. By using developed program for tangential cam mechanism, we designed tangential cam models and analysed displacement, velocity, acceleration of follower.