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Ignition and flame propagation for pyrolysing fuel in a cylindrical enclosure has been examined in this study. The pyrolysing fuel of cylindrical shape was located both eccentrically and concentrically inside an outer cylinder that was sustained at high temperature. Due to gravity, buoyancy motion was inevitably incurred in the enclosure, and this was found to affect the flame initiation and propagation behaviour. Radiative heat transfer also played an important role in the thermo-fluid mechanical behaviour because of the high temperature involved in the problem. Numerical studies have been performed for various parameters such as the Grashof number, overheat ratio, gas absorption coefficient and vertical fuel eccentricity. The flame behaviour and initiation were observed to be totally different depending on the Grashof number. Due to absorbed radiant energy, the radiative gas played a significant role in flame evolution. The location of flame onset was also affected by both the vertical eccentricity of the inner pyrolysing fuel and the thermal conditions applied. The heating process and the flow field development were found to govern flame initiation and propagation. 相似文献
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Many different types of urine proteome studies have been done, but urine glycoprotein studies are insufficient. Therefore, we studied the glycoproteins from rat urine, which could be used to identify biomarkers in an animal model. First, urinary proteins were prepared by using the dialysis and lyophilizing methods from rat urine. Glycoproteins enriched with lectin affinity purification, concanavalin A, jacalin and wheat germ agglutinin from the urinary proteins were separated by means of reverse-phase fast protein LC (FPLC) or 1-D PAGE. Each FPLC fraction and 1-D PAGE gel band were trypsin-digested and analyzed by means of nanoLC-MS/MS. LC-MS/MS analyses were carried out by using linear ion trap MS. A total of 318 rat urinary glycoproteins were identified from the FPLC fractions and gel bands; approximately 90% of identified proteins were confirmed as glycoproteins in Swiss-Prot. Many glycoproteins, known as biomarkers, including C-reactive protein, uromodulin, amyloid beta A4 protein, alpha-1-inhibitor 3, vitamin D-binding protein, kallikrein 3 and fetuin-A were identified in this study. By studying urinary glycoproteins collected from rat, these results may help to assist in identifying urinary biomarkers regarding various types of disease models. 相似文献
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Wanchanok Nantacharoen Seung Joon Baek Waluga Plaingam Somsri Charoenkiatkul Tewin Tencomnao Monruedee Sukprasansap 《Molecules (Basel, Switzerland)》2022,27(18)
Excessive glutamate neurotransmitters result in oxidative neurotoxicity, similar to neurodegeneration. An indigenous berry of Thailand, Cleistocalyx nervosum var. paniala (CNP), has been recognized for its robust antioxidants. We investigated the effects and mechanisms of CNP fruit extracts on antioxidant-related survival pathways against glutamate-induced neurotoxicity. The extract showed strong antioxidant capability and had high total phenolic and flavonoid contents, particularly resveratrol. Next, the protective effects of the CNP extract or resveratrol on the glutamate-induced neurotoxicity were examined in HT22 hippocampal cells. Our investigation showed that the pretreatment of cells with the CNP extract or resveratrol attenuated glutamate-induced neuronal death via suppression of apoptosis cascade by inhibiting the levels of cleaved- and pro-caspase-3 proteins. The CNP extract and resveratrol suppressed the intracellular ROS by increasing the mRNA expression level of antioxidant enzymes (SODs, GPx1, and CAT). We found that this extract and resveratrol significantly increased SIRT1 expression as a survival-related protein. Moreover, they also promoted the activity of the Nrf2 protein translocation into the nucleus and could bind to the promoter containing the antioxidant response element, inducing the expression of the downstream GPx1-antioxidant protein. Our data illustrate that the CNP extract and resveratrol inhibit apoptotic neuronal death via glutamate-induced oxidative neurotoxicity in HT22 cells through the activation of the SIRT1/Nrf2 survival mechanism. 相似文献
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Do-Gyeong Lee Dae-Young Lee Myeng-Chong Song Jin-Gyeong Cho Myun-Ho Bang Nam-In Baek 《Chemistry of Natural Compounds》2010,46(3):338-339
A new compound, 4-O-(6'-O-p-hydroxybenzoyl-β-D-glucopyranosyl)-cis-p-coumaric acid, was isolated from the fruits of hot pepper (Capsicum annuum L.). The structure of the compound was established on the basis of NMR, FAB-MS, and IR spectroscopic data. 相似文献
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Hohyun Kim Jae-Yong Lee Ki-Seob Song Young-Hwan Seo So-Young Park Kyeong-Ho Kim Hyun Dong Je Sang Beom Han Ji Hoon Jeong 《Chromatographia》2010,71(7-8):595-602
A sensitive, selective, and simple liquid chromatography-tandem mass spectrometry method has been developed for the simultaneous separation and determination of isosorbide dinitrate and its active metabolite, isosorbide 5-mononitrate, in human plasma. Topiramate was used as the internal standard. Sample preparation consisted of a simple one-step liquid–liquid extraction with ethylacetate without pH adjustment. The method was fully validated with respect to linearity, sensitivity, specificity, recovery, accuracy, and precision. Isosorbide dinitrate and isosorbide 5-mononitrate were stable in standard solution and in plasma samples under storage and processing conditions. The assay was successfully applied to the pharmacokinetic study of isosorbide dinitrate and isosorbide 5-mononitrate in human plasma. 相似文献
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Amarender Manchoju Renaud Zelli Gang Wang Carla Eymard Adrian Oo Mona Nemer Michel Prvost Baek Kim Yvan Guindon 《Molecules (Basel, Switzerland)》2022,27(2)
The design of novel nucleoside triphosphate (NTP) analogues bearing an all-carbon quaternary center at C2′ or C3′ is described. The construction of this all-carbon stereogenic center involves the use of an intramoleculer photoredox-catalyzed reaction. The nucleoside analogues (NA) hydroxyl functional group at C2′ was generated by diastereoselective epoxidation. In addition, highly enantioselective and diastereoselective Mukaiyama aldol reactions, diastereoselective N-glycosylations and regioselective triphosphorylation reactions were employed to synthesize the novel NTPs. Two of these compounds are inhibitors of the RNA-dependent RNA polymerase (RdRp) of SARS-CoV-2, the causal virus of COVID-19. 相似文献
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