• 동의신경정신과학회지
• /
• 제11권2호
• /
• pp.1-9
• /
• 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.

• 동의신경정신과학회지
• /
• 제11권1호
• /
• pp.37-46
• /
• 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.

• Preventive Nutrition and Food Science
• /
• 제12권4호
• /
• pp.251-258
• /
• 2007

Thermal resistance and heat activation characteristics of Clostridium botulinum ATCC 25763 spores were evaluated. The effects of nisin and pH on the activation and subsequent germination were also investigated. Spores of C. botulinum were not inactivated by heat treatments up to $92^{\circ}C$ for 2 hr. Heat treatment at $85^{\circ}C$ for 90 min was selected as the optimal activation condition based on monitoring subsequent germination. L-alanine alone or in combination with L-cysteine was not sufficient to germinate the spores of this strain. Tryptone-Peptone- Glucose-Yeast extract (TPGY) broth supplemented with L-alanine was used as a suitable germination medium. Decreasing pH of activation suspension increased the degree of phase darkening, i.e., germination. In addition, the presence of nisin during activation increased the degree of phase darkening. The majority of spore populations were dormant at a pH of less than 2.8, and these populations required heat activation to increase the culturability on TPGY agar medium. However, extended heating in the presence of nisin at pH 2.8 decreased the spore count; however, heat activation was less necessary at pH 3.4, compared at pH 2.8.

• 한국화재소방학회논문지
• /
• 제34권3호
• /
• pp.35-42
• /
• 2020

성능위주 소방설계(PBD)의 안전성 평가 과정에서 화재모델링의 신뢰성 확보를 위해서는 화재감지기 작동시간의 정확한 예측성능이 요구된다. 본 연구는 대표적 화재모델인 FDS에 적용되는 정온식 열감지기의 주요 입력인자인 감지기 작동온도와 RTI의 측정을 목표로 한다. 이를 위해 화재감지기 실험 장치인 Fire detector evaluator (FDE)가 적용되었으며, 제품 인지도 조사를 통해 선정된 국내 10종의 정온식 감지기가 고려되었다. 결과적으로 감지기의 제조사별로 작동온도와 RTI는 상당한 차이가 있는 것으로 확인되었으며, 측정된 DB가 적용된 FDS의 감지기 작동시간은 보다 정확한 예측이 가능함을 확인하였다. 최종적으로 신뢰성이 확보된 정온식 열감지기의 작동온도와 RTI의 DB가 제공되었다.

• Bulletin of the Korean Chemical Society
• /
• 제34권11호
• /
• pp.3405-3409
• /
• 2013

The activation of heat shock factor 1 (HSF1) can be induced by the changes in environmental pH, but the mechanism of HSF1 activation by acidification is not completely understood. This paper reports that a low pH (pH~6.0) can trigger human HSF1 activation. Considering the involvement of the imidazole group of histidine residues under acid pH stress, an in vitro EMSA experiment, Trp-fluorescence spectroscopy, and protein structural analysis showed that the residue, His83, is the essential for pH-dependent human HSF1-activation. To determine the roles of His83 in the HSF1-mediated stress response affecting the cellular acid resistance, mouse embryo fibroblasts with normal wild-type or mutant mouse HSF1 expression were preconditioned by heating or pH stress. The results suggest that His83 is essential for HSF1 activation or the HSF1-mediated transcription of heat shock proteins, in protecting cells from acid pH stress.

• 한국표면공학회지
• /
• 제47권6호
• /
• pp.275-281
• /
• 2014

An ultrasound-assisted Sn-Ag-Pd activation method for electroless copper plating was presented in this study. With this activation process, it was shown that the fine catalyst particles were homogeneously distributed with high density on the entire specimen. In addition, it was observed that incubation period occurred during the electroless plating step was decreased owing to the absorption of Ag which holds high catalytic activity. Resulting from the refinement and high densification of catalyst, the defect-free gap-fill was achieved within the 20x nm trench.

• 전기학회논문지
• /
• 제61권9호
• /
• pp.1358-1361
• /
• 2012

This paper presents a study on the analysis for activation time and threshold value of heat detection sensor using HRR(Heat Release Rate). And it is represented to quantity of heat to activate heat detection sensor. The experiment is conducted to measure activation time and HRR of fire detection sensor burning alcohol and n-heptane. In order to burn the alcohol and n-heptane using $43.5cm(L){\times}43.5cm(W){\times}5cm(D)$ and $33cm(L){\times}33cm(L){\times}5cm(D)$ steel pan and the quantity of alcohol and n-heptane are 2.5 L and 650 g, respectively. The results show that peak HRR are in case of alcohol 66.13 kW and in case of n-heptane 151.64 kW, respectively. Total heat releases of heat detection sensor are in case of alcohol approximately 20.7 MJ and in case of n-heptane approximately 18 MJ, respectively.

• 한국환경과학회지
• /
• 제26권11호
• /
• pp.1201-1208
• /
• 2017

Oxidative degradation of chlorinated ethenes was carried out using heat-activated persulfate. The activation rate of persulfate was dependent on the temperature and the activation reaction rate could be explained based on the Arrhenius equation. The activation energy of persulfate was 19.3 kcal/mol under the assumption that the reaction between the sulfate radical and tricholoroethene (TCE) is very fast. Activation could be achieved at a moderate temperature, so that the adverse effects due to high temperature in the soil environment were mitigated. The reaction rate of TCE was directly proportional to the concentration of persulfate, indicating that the remediation rate can be controlled by the concentration of the injected persulfate. The solution was acidized after the oxidation, and this was dependent on the oxidation temperature. The consumption rate of persulfate was high in the presence of the target organic, but the self-decomposition rate became very low as the target was completely removed.

• 동의신경정신과학회지
• /
• 제10권2호
• /
• pp.47-57
• /
• 1999

Recently, essential oils are used for aromatherapy. Most essential oils are said to be anti-bacterial; some may be anti-viral or anti-fungal. I investigated the effects of peppermint pure essential oil on the heat shock-induced apoptosis in human astrocyte cell line CCF-STTGI. In previous studies, heat shock has been reported to induce the apoptosis or programmed cell death through the activation of caspase-3. We studied the heat shock-induced apoptosis through flow cytometry, DNA electrophoresis, and giemsa staining. Interestingly, these events were inhibited by pretreatment of peppermint pure essential oils in CCF-STTGl cells. Peppermint oil also inhibited the heat shock-induced apoptosis in primary cultured rat astrocytes. In addition, this Peppermint essential oil inhibited the heat shock-induced activation of caspase-3. These results suggest that peppermint pure essential oils may modulate the apoptosis through the activation of the interleukin-I -converting enzyme-like protease.

• 한국재료학회:학술대회논문집
• /
• 한국재료학회 2012년도 춘계학술발표대회
• /
• pp.91.2-91.2
• /
• 2012

The TiB2-reinforced iron matrix nanocomposite (Fe-TiB2) was in-situ fabricated from titanium hydride (TiH2) and iron boride (FeB) powders by a simple and cost-effective process that combines the mechanical activation (MA) and a subsequent heat treatment (HT). Effect of milling factors and synthesized temperatures on the formation of the nanocomposite were presented and discussed. A differential thermal analyser (DSC-TG) was employed for examination of thermal behavior of MAed powders. Phases of the nanocomposite were confirmed by X-ray diffraction analysis (XRD). The morphologies and microstructure of nanocomposite were investigated by field emission-scanning electron microscopy (FE-SEM) and energy-dispersive X-ray spectroscopy (EDS). Phase composition and distribution were analyzed by electron probe X-ray microanalysis (EPMA). Results showed that TiB2 particles formed in nanoscale were uniformly distributed in alloyed Fe matrix.