• International Journal of Railway
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• v.4 no.4
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• pp.103-108
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• 2011

The effect of the core cell shape on shock absorption characteristics of biomimetically inspired honeycomb structures has been numerically investigated. The finite element models of honeycomb test specimen composed of five core cells of identical mass have been constructed, and numerical simulations have been run on PAMCRASH. The dimensions of the sides of core cells as well as the angle between the sides have been shown to influence the shock absorption characteristics of the honeycomb structure. The specimen with regular hexagonal core cell shape is found to show the best shock absorbing capacity, and specimen with rectangle-like core cell are found to provide good shock absorbing characteristics.

• Molecules and Cells
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• v.23 no.2
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• pp.123-131
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• 2007

Extracellular stresses induce heat shock response and render cells resistant to lethal stresses. Heat shock response involves induction of heat shock proteins (Hsps). Recently the roles of Hsps in neurodegenerative diseases and cancer are attracting increasing attention and have accelerated the study of heat shock response mechanism. This review focuses on the stress sensing steps, molecules involved in Hsps production, diseases related to Hsp malfunctions, and the potential of proteomics as a tool for understanding the complex signaling pathways relevant to these events.

• Journal of Periodontal and Implant Science
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• v.33 no.4
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• pp.543-553
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• 2003

Due to considerably high degree of sequence homology between bacterial and human heat shock proteins(hsp), it has been widely thought that this protein might be involved in autoimmune disease mechanisms in humans. To elucidate how stress proteins contribute in the immunopathogenesis of periodontitis, the present study was performed to evaluate the T cell immune responses specific to Porphyromonas gingivalis (P. gingivalis) heat shock protein (hsp)60 and T-cell epitope specificities for P. gingivalis hsp60 in periodontitis. Anti-P. gingivalis IgG antibody titers were elevated in all patients. We could establish P. gingivalis hsp-specific T cell ines from the peripheral blood of peridontitis, a mixture of $CD4^+$ and $CD8^+$ cells. Of 108 overlapping synthetic peptides spanning whole P. gingivalis hsp60 moleculc, ten peptides with cpitopes specifities for T-cell were showed. Interestingly, ten epitopes were also identified as T-cell epitopes in the present study as well as B-cell epitopes in peridontitis. Therefore, all the ten representative epitopes were designated as common T-and B-cell epitopes for peridontitis. It is critical in developing a peptide vaccine strategy for potential prevention of periodontitis. It was concluded that P. gingivalis hsp60 might be involved in the immunoregulatory process of periodontitis with heat shock protein specificities.

• Journal of Oriental Neuropsychiatry
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• v.11 no.1
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• pp.37-46
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• 2000

We investigated the effects of lemon pure essential oils on the heat shock-induced apoptosis in human astrocyte cell line CCF-STTG1. In previous studies, hear shock has been reported to induce the apoptosis or programmed cell death through the activation of caspase-3. Treatment of CCF-STTG1 cells with heat shock markedly induced apoptotic cell death as determined by flow cytometry. Interestingly, pretreatment of CCF-STTG1 cells with lemon pure essential oils inhibited the heat shock-induced apoptosis. Lemon also inhibited the heat shock-induced apoptosis in primary cultured rat astrocytes. To determine whether lemon inhibits the heat shock-induced activation of these apoptotic proteases, activation of CPP32 was assessed by Western blotting. Consistent with flow cytometry, DNA fragmentation and giemsa staining, heat shock-induced activation of CPP32 was blocked by lemon pure essential oil. PARP, cysteine protease substrates were fragmented as a consequence of apoptosis by heat shock. Lemon oil inhibited the PARP fragmentation. This essential oil also inhibited the heat shock-induced activation of caspase-3. These results suggest that lemon pure essential oils may modulate the apoptosis through the activation of the ICE-like caspases.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.784-788
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• 2004

A visualization study of shock formation of the supersonic jet nozzle using a Shadowgraph Method (SM) was carried out to investigate the effect of the longitudinal variation of coaxial pipe end tip position inside the supersonic nozzle. The experiment was performed for the Mach number range from 1.1 to 1.2 at nozzle exit. The well known shock cell structure was shown with the pipe end located deep inside the nozzle for the studied Mach number. With the pipe end approaches nozzle exit, it was found that the shock cell structure disappeared and turned into complex formation. In order to understand the mechanism of the shock structural change, computational simulation was carried out using the Navier-Stokes solver, FLUENT. Topological sketch was added with an aid of the visualization and the numerical simulation.

• Journal of Oriental Neuropsychiatry
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• v.11 no.2
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• pp.1-9
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• 2000

In previous studies, heat shock has been reported to induce the apoptosis or programmed cell death through the activation of caspase-3. 1 investigated the effect of juniper pure essential oil on the heat shock-induced apoptosis in human astrocyte cell line CCF-STTGI. Treatment of the astrocytes with heat shock markedly induced apoptotic cell death. However, pretreatment of the astrocytes with juniper oil ingibited the heat shock-induced apoptosis. To determine whether juniper inhibits the heat shock-induced activation of these apoptotic proteases, activation of CPP32 was assessed by Western blotting. Consistent with flow cytometry. DNA fragmentation and giemsa staining, heat shock-induced activation of CPP32 was blocked by juniper oil. Poly(ADP-ribose) polymerase (PARP), cysteine protease substrates were fragmented as a consequence of apoptosis by heat shock. Juniper oil inhibited the PARP fragmentation. This juniper oil also inhibited the heat shock-induced activation of caspase-3. These results suggest that juniper oil may modulate the apoptosis through the activation of the interleukin-1-converting enzyme-like protease.

• Journal of Energy Engineering
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• v.21 no.1
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• pp.26-32
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• 2012

This study has been performed Thermal Shock test for analyze the cause of Power drop in PV(Photovoltaic) Module. Thermal Shock test condition was performed with temperature range from $-40^{\circ}C{\sim}85^{\circ}C$. One cycle time is 30min. which are consist of low and high temperature 15min. each other. The test was performed with total 500cycles. EL, I-V were conducted every 100cycle up to 500cycles. Mono Cell resulted in 8% Power drop rates in Bare Cell and 9% in Solar Cell. In the case of Multi Cell resulted in 6% Power drop rates in Bare Cell and 13% in Solar Cell. After Thermal Shock test, Solar Cell's Power drop resulted from surface damages, but in the case of Bare Cell's Power drop had no surface damages. Therefore, Bare Cell's Power drop was confirmed as according to leakage current increase by analysis of Fill Factor after Thermal Shock test. Also, Solar Cell's Power drop rates are higher than that of Bare Cell because of surface damages and consuming electric power increase. From now on, it should be considered that analyzed the reasons of Fill Factor decrease and irregular Power drop in PV module and Cell level using cross section, various conditions and test methods.

• 한국전산유체공학회:학술대회논문집
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• 2002.10a
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• pp.103-108
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• 2002

The M-AUSMPW+ scheme that can capture shock waves exactly with monotonic characteristics is modifided from AUSMPW+ by analyzing the cause of oscillation in shock regions. Firstly shock-capturing characteristics of general FVS including the AUSM-type schemes are investigated in detail, according to the difference between a cell-interface and a sonic transition position. The cause of oscillation is the improper numerical dissipation that could not represent the real Physics. The M-AUSMPW+ could capture shocks exactly without oscillatory behaviors in considering the sonic transition position and an cell-interface position.

• Mass Spectrometry Letters
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• v.7 no.1
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• pp.1-11
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• 2016

Various efforts have been developed to improve sample preparation steps, which strongly depend on hands-on processes for accurate and sensitive quantitative proteome analysis. In this study, we carried out heating the sample prior to trypsin digestion using an instrument to improve the tryptic digestion process. The heat shock generated by the system efficiently denatured proteins in the sample and increased the reproducibility in quantitative proteomics based on peptide abundance measurements. To demonstrate the effectiveness of the protocol, three cell lines (A human lung cancer cell line (A549), a human embryonic kidney cell line (HEK293T), and a human colorectal cancer cell line (HCT-116)) were selected and the effect of heat shock was compared to that of normal tryptic digestion processes. The tryptic digests were desalted and analysed by LC-MS/MS, the results showed 57 and 36% increase in the number of identified unique peptides and proteins, respectively, than conventional digestion. Heat shock treated samples showed higher numbers of shorter peptides and peptides with low inter-sample variation among triplicate runs. Quantitative LC-MS/MS analysis of heat shock treated sample yielded peptides with smaller relative error percentage for the triplicate run when the peak areas were compared. Exposure of heat-shock to proteomic samples prior to proteolysis in conventional digestion process can increase the digestion efficiency of trypsin resulting in production of increased number of peptides eventually leading to higher proteome coverage.

• Journal of Microbiology and Biotechnology
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• v.4 no.1
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• pp.30-35
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• 1994

A varient strain of budding yeast, Hansenula anomala B-7 which had been identified to be highly resistant to cadmium ions, were observed by transmission electron microscopy. It was shown that the cells accumulated excess amounts of cadmium ions throughout inside the cell rather than on the cell surface. The cell growth in response to cadmium or heat shock stress has also been investigated. It was observed that the cells precultured in the presence of 500 $\mu$ g/ml of Cd ions grew slower than those precultured at 1, 000 $\mu$ g/ml of the metal ions, when they were cultivated in the media containing 1, 000 $\mu$g/ml of the metal ions. Heat shock, however, stimulated the cell growth transiently, when the cells were allowed to grow in the presence of 1, 000 $\mu$g/ml of the metal ions. But the cells given heat shock for more than 100 min received permanent damage to growth. Effects of both stresses on budding rate was also examined. It revealed that the stresses did not change the budding ratio much, which was contradictory to that observed from the same budding yeast, Saccharomyces cerevisiae. Furthermore, the cells treated with 1, 000 $\mu$g/ml of the metal ions not only induced, but also switched off the expression of several new proteins. Some of the cadmium stress-inducible proteins were estimated to be also induced by heat shock stress.