• Title/Summary/Keyword: Pretreatment temperature

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The Effect of Heat Shock Response on the Tumor Necrosis Factor-$\alpha$-induced Acute Lung Injury in Rats (Tumor Necrosis Factor-$\alpha$로 유도되는 백서의 급성 폐손상에 열충격반응이 미치는 효과)

  • Koh, Youn-Suck;Lim, Chae-Man;Kim, Mi-Jung;Cho, Won-Kyung;Jeoung, Byung-O;Song, Kyu-Young;Shim, Tae-Sun;Lee, Sang-Do;Kim, Woo-Sung;Kim, Dong-Soon;Kim, Won-Dong
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.6
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    • pp.1343-1352
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    • 1997
  • Background : Heat-treated cells are known to be protected from lysis by TNF, which is considered to play a central role in the pathogenesis of sepsis-induced acute lung injury. The objective of the study was to investigate the effect of heat shock response by heat-pretreatment on the acute lung injury of the rats induced by intratracheally administered TNF-$\alpha$, Methods : We intratracheally instilled either saline or TNF (R&D, 500ng) with and without heat pretreatment in Sprague-Dawley rats weighing 250~350 g. The heated rats were raised their rectal temperature to $41^{\circ}C$ and was maintained thereafter for 13 minutes at 18 h before intratracheal administration of saline or TNF. After 5 h of intratracheal treatment, lung leak, lung myeloperoxidase activity (MPO) and heat shock proteins were measured in rats. Lung leak index was defined as counts per minute of $I^{25}$ in the right lung divided by counts per minutes of $I^{25}$ in 1.0 ml of blood. All data are expressed as means ${\pm}$SE. Results : There is no difference in acute lung leak index ($0.099{\pm}0.024$ vs $0.123{\pm}0.005$) among the rats given saline intratracheally with and without heat pretreatment, but MPO activity showed a decreased tendency in heat-pretreated rats ($4.58{\pm}0.79\;U/g$) compared with heat-unpretreated rats ($7.32{\pm}0.97\;U/g$) (P=0.064). Rats administered TNF intratracheally with heat-pretreatment had decreased lung leak index ($0.137{\pm}0.012$) and lung MPO activity ($5.51{\pm}1.04\;U/g$) compared with those of heat-unpretreated and TNF-administered rats ($0.186{\pm}0.016$, $14.34{\pm}1.22\;U/g$) (P<0.05 in each). There were no significant difference of lung leak index and MPO activity between TNF-treated rats with heat-pretreatment and saline-treated rats with and without heat-pretreatment. Conclusion : The heat shock response attenuated neutrophil recruitment and acute lung leak induced by intratracheal instillation of TNF-in rats.

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Study on Pretreatment Methods to Prevent Tissue Softening of Heated Onion (가열 양파의 조직 연화 방지를 위한 전처리 방법에 관한 연구)

  • Choi, Jun-Bong;Cho, Won-Il
    • Korean Journal of Food Science and Technology
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    • v.47 no.1
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    • pp.56-62
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    • 2015
  • Various pretreatment methods were evaluated to prevent tissue softening of heated onion. Changes in onion tissue firmness during heating were explained by 3-mechanism model consisting of texture hardening at low temperature ($60-80^{\circ}C$) and substrate softening at high temperature. Preheating of onion in a $Ca^{2+}$-containing solution significantly improved its texture after high-temperature heating. The improvement of firmness by preheating at low temperature was related to the formation of strong cross-linking between carboxyl groups and $Ca^{2+}$ by the action of pectin methylesterase in onion. The highest firmness was obtained by pre-heating at $70^{\circ}C$ for 120 min in 0.5% calcium solution. This result was supported by chemical analysis showing that the amount of bound calcium was the highest at $70^{\circ}C$. Further investigation should be carried out to establish the optimal conditions to prevent the softening of various vegetables.

Changes in the Quality of Hallabong Tangor(Citrus kiyomi ${\times}$ ponkan) with Growth Stage and Temperature Pretreatment Conditions (생육단계와 온도처리에 따른 한라봉 감귤의 품질변화)

  • Lee, Sang-Hyup;Kim, Jong-Hun;Jeong, Hee-Chan;Koh, Jeong-Sam
    • Food Science and Preservation
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    • v.14 no.6
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    • pp.565-570
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    • 2007
  • Changes in the quality of Hallabong tangor during growth stage and with temperature pre-treatment after harvest were investigated. Soluble solids of Hallabong increased continuously until early December. The acid content of M16A, a variant species of Hallabong, decreased by 1% after October and continued to decrease until the middle of January. After ripening, treatment to reduce the acid content was required. Fruit firmness decreased gradually until November and was maintained at 1000 g-force after this time. Soluble solids and acid content were $13.3{\pm}0.83^{\circ}Brix$ and $1.07{\pm}0.52%$. Soluble solids increased in temperature-treated Hallabong with prolonged storage, but acid content did not decrease. Fruit firmness also decreased with storage period, regardless of temperature pre-treatment. Therefore, water management during cultivation, temperature treatment above $35^{\circ}C$ after harvest, and checking of the acid content and soluble solids with prolonged storage are recommended in achieving high quality Hallabong.

Enhanced Tolerance of Chinese Cabbage Seedlings Mediated by Bacillus aryabhattai H26-2 and B. siamensis H30-3 against High Temperature Stress and Fungal Infections

  • Lee, Young Hee;Jang, Su Jeong;Han, Joon-Hee;Bae, Jin Su;Shin, Hyunsuk;Park, Hee Jin;Sang, Mee Kyung;Han, Song Hee;Kim, Kyoung Su;Han, Sang-Wook;Hong, Jeum Kyu
    • The Plant Pathology Journal
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    • v.34 no.6
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    • pp.555-566
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    • 2018
  • Two rhizobacteria Bacillus aryabhattai H26-2 and B. siamensis H30-3 were evaluated whether they are involved in stress tolerance against drought and high temperature as well as fungal infections in Chinese cabbage plants. Chinese cabbage seedlings cv. Ryeokgwang (spring cultivar) has shown better growth compared to cv. Buram-3-ho (autumn cultivar) under high temperature conditions in a greenhouse, whilst there was no difference in drought stress tolerance of the two cultivars. In vitro growth of B. aryabhattai H26-2 and B. siamensis H30-3 were differentially regulated under PEG 6000-induced drought stress at different growing temperatures (30, 40 and $50^{\circ}C$). Pretreatment with B. aryabhattai H26-2 and B. siamensis H30-3 enhanced the tolerance of Chinese cabbage seedlings to high temperature, but not to drought stress. It turns out that only B. siamensis H30-3 showed in vitro antifungal activities and in planta crop protection against two fungal pathogens Alternaria brassicicola and Colletotrichum higginsianum causing black spots and anthracnose on Chinese cabbage plants cv. Ryeokgwang, respectively. B. siamensis H30-3 brings several genes involved in production of cyclic lipopeptides in its genome and secreted hydrolytic enzymes like chitinase, protease and cellulase. B. siamensis H30-3 was found to produce siderophore, a high affinity iron-chelating compound. Expressions of BrChi1 and BrGST1 genes were up-regulated in Chinese cabbage leaves by B. siamensis H30-3. These findings suggest that integration of B. aryabhattai H26-2 and B. siamensis H30-3 in Chinese cabbage production system may increase productivity through improved plant growth under high temperature and crop protection against fungal pathogens.

A Process for Preventing Enzymatic Degradation of Rutin in Tartary Buckwheat (Fagopyrum tataricum Gaertn) Flour

  • Li, Dan;Li, Xiaolei;Ding, Xiaolin;Park, Kwan-Hwa
    • Food Science and Biotechnology
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    • v.17 no.1
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    • pp.118-122
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    • 2008
  • The use of tartary buckwheat flour as a source of dietary rutin has been limited because of the enzymatic degradation of rutin during the dough-making process, which results in a bitter taste. A variety of pretreatment regimes, including heating, steaming, boiling, and extruding, were evaluated in relation to the inactivation of the rutin-degrading enzyme responsible for rutin loss and color change during dough-making. Steaming (120 see), boiling (90 see) buckwheat grains, or extruding (180 rpm/min at $140^{\circ}C$) the flour resulted in the retention of >85% of the original rutin and eliminated the bitter taste in the hydrated flours. In contrast, dry heating at $140^{\circ}C$ for 9 min or microwaving at 2,450 MHz for 3 min did not reduce the rutin loss, and the bitter taste remained. Unlike in the flour, the rutin degradation in water-soaked grains was insignificant at room temperature. Moreover, the samples treated by steaming, boiling, or extrusion were darker and more reddish in color.

The Effect of Pretreatment of Raw Powders on the Photoluminescence of Ca-α-SiAlON:Eu2+ Phosphor

  • Park, Young-Jo;Kim, Jin-Myung;Lee, Jae-Wook
    • Journal of the Korean Ceramic Society
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    • v.51 no.5
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    • pp.413-417
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    • 2014
  • The effect of calcination treatment of raw powders prior to high temperature synthesis of Ca-${\alpha}$-SiAlON:$Eu^{2+}$ phosphor was investigated. Based on data acquired from thermogravimetric analysis, calcination temperatures were set at 600, 750, and $900^{\circ}C$. Compared to the photoluminescence (PL) intensity of direct synthesis without calcination, a similar intensity was found for the $600^{\circ}C$ treatment, a 19% increased PL intensity was found for the $750^{\circ}C$ treatment, and a 23% decreased PL intensity was found for the $900^{\circ}C$ treatment. Observation of the particle morphology of the synthesized phosphors revealed that the material transport promoted through the agglomerates formed by the $750^{\circ}C$ treatment led to enhanced PL intensity. On the other hand, the oxidation of the starting AlN particles during the $900^{\circ}C$ treatment resulted in decreased photoluminescence.

Surface Passivation of Tunnel Silicon Oxide Grown by Ozone Oxidation (오존 산화에 의해 형성된 터널 실리콘 산화막의 표면 패시베이션)

  • Baek, Jong Hoon;Cho, Young Joon;Chang, Hyo Sik
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.31 no.5
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    • pp.341-344
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    • 2018
  • In order to achieve a high efficiency for the silicon solar cell, a passivation characteristic that minimizes the electrical loss at a silicon interface is required. In this paper, we evaluated the applicability of the oxide film formed by ozone for the tunnel silicon oxide film. To this end, we fabricated the silicon oxide film by changing the condition of ozone oxidation and compared the characteristics with the oxide film formed by the existing nitric acid solution. The ozone oxidation was formed in the temperature range of $300{\sim}500^{\circ}C$ at an ozone concentration of 17.5 wt%, and the passivation characteristics were compared. Compared to the silicon oxide film formed by nitric acid oxidation, implied open circuit voltage (iVoc) was improved by ~20 mV in the ozone oxidation and the ozone oxidation after the nitric acid pretreatment was improved by ~30 mV.

Study on the Synthesis of Alumina Membrane by Anodization in Sulfuric Acid (황산전해액에서 양극산화에 의한 알루미나 막 제조에 관한 연구)

  • Kim, Hyun;Chang, Yoon Ho;Hahm, Yeong Min
    • Applied Chemistry for Engineering
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    • v.8 no.5
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    • pp.756-762
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    • 1997
  • The experiment was carried out to fabricate alumina membrane which has a cylindrical pore structure by anodizing aluminium plate in sulfuric acid solution with the electrochemical technique. The aluminium plate for anodizing was prepared by the pretreatment process such as chemical, electro-polishing and thermal treatment. The pore size distribution and the film thickness of alumina membrane were investigated by the implementation of scanning electron microscope(SEM) and BET method. The results show that the oxide film has a geometrical structures like a Keller model and that the membrane has a uniform pore distribution. The pore size and the oxide film thickness are dependent on the anodizing process variables such as the electrolyte concentration, the reation temperature and the anodizing current density.

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Characterization of Toxic Pollutants in Ash and Flue Gas from Gasification Incinerator of Waste Tires (폐타이어 건류 소각에서 발생되는 재와 배기 가스에서의 독성 오염 물질의 정량)

  • Koo, Ja Kong;Seo, Young Hwa;Kim, Seok Wan;Yoo, Dong Joon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.13 no.1
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    • pp.213-220
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    • 1993
  • The problem of disposing of huge quantities of used tires is of growing concern to every country. As an economical solid waste management, a gasification followed by incineration process was applied to scrap tires to recover heat and to reduce waste volume for final landfill disposal. The gasification temperature, combustible and non-combustible gasified products and possibly produced air pollutants were predicted by changing equivalent mole ratios of carbon to oxygen by a chemical equilibrium model. For a risk assessment of ash toxic pollutants including heavy metals and toxic organics were thoroughly analyzed. Gasification bottom ash contained much more toxic organic compounds than fly ash, whereas fly ash contained higher concentration of heavy metals such as Pb and Cd. Pretreatment or secure landfill technology is suggested for a safe management of ash produced from the gasification incinerators.

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The characteristics of AlN buffered GaN on ion implanted Si(111) (이온주입된 Si(111)에 AlN 완충층을 이용하여 성장시킨 GaN 박막의 특성)

  • 강민구;진정근;이재석;노대호;양재웅;변동진
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2003.11a
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    • pp.165-165
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    • 2003
  • The growth of GaN on Si is of great interest due to the several advantages low cost, large size and high-quality wafer availability as well as its matured technology. The crystal quality of GaN is known to be much influenced by the surface pretreatment of Si substrate [1]. In this work, the properties of GaN overlayer grown on ion implanted Si(111)and bare Si(111) have been investigated. Si(111) surface was treated ion implantation with 60KeV and dose 1${\times}$10$\^$16//$\textrm{cm}^2$ prior to film growth. GaN epilayers were grown at 1100$^{\circ}C$ for 1 hour after growing AlN buffer layers for 15-30 minutes at 1100$^{\circ}C$ with metal organic chemical vapor deposition (MOCVD). The properties of GaN epilayers were evaluated by X-Ray Diffraction (XRD), Scanning electron microscope (SEM) Photoluminescence (PL) at room temperature and Hall measurement The results showed that the GaN on ion implanted Si(111) markedly affected to the structural, optical and electrical characteristic of GaN layers.

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