860 resultados para Tobacco--Poetry
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Microcystins are cyclic heptapeptide hepatoxins produced by cyanobacteria. It has been shown that microcystins have adverse effects on animals and on plants as well. Previous researches also indicated that microcystins were capable of inducing oxidative damage in animals both in vivo and in vitro. In this study, tobacco BY-2 suspension cell line was applied to examine the effects of microcystin-RR on plant cells. Cell viability and five biochemical parameters including reactive oxygen species (ROS), superoxide dismutase (SOD), catalase (CAT), glutathione peroxide (GPX) and peroxide dismutase (POD) were investigated when cells were exposed to 50 mg/L microcystin-RR. Results showed that microcystin-RR evoked decline of the cell viability to approximately 80% after treating for 144 h. ROS levels, POD and GPX activities of the treated cells were gradually increased with a time dependent manner. Changes of SOD and CAT activities were also detected in BY-2 cells. After 168 h recovery, ROS contents, POD, GPX and CAT activities returned to normal levels. These results suggest that the microcystin-RR can cause the increase of ROS contents in plant cells and these changes led to oxidant stress, at the same time, the plant cells would improve their antioxidant abilities to combat mirocystin-RR induced oxidative injury. (c) 2005 Elsevier Ltd. All rights reserved.
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A sorbent showing specific affinity for nicotine was prepared by molecular imprinting technique, using nicotine as the template, methacrylic acid (MAA) as the functional monomer, ethyleneglycol dimethacrylate (EDMA) as the crosslinker and chloroform as the porogen. UV spectroscopic analysis in the molecular imprinting prepolymerization stage confirmed that nicotine could complex with the functional monomer by electrostatic interaction (ionic interaction and hydrogen bonding). The affinity and the binding properties of the imprinted polymer towards nicotine were investigated by equilibrium rebinding experiments. The results indicated the presence of nicotine-specific binding sites in the imprinted polymer, and that the imprinted polymer had a good capacity (90 mumol/g polymer) for nicotine. The elution conditions were optimized on the column packed with the imprinted polymer to elute nicotine quantitatively. The imprinted polymer was used as a solid-phase extraction (SPE) material for the removal of nicotine from tobacco smoke. The results obtained showed that the imprinted polymer was superior in terms of removing nicotine in tobacco smoke, compared with the commercial filter tip.
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A sample of tobacco essential oil was analyzed using gas chromatography-mass spectrometry (GUMS)and comprehensive two-dimensional gas chromatography coupled to a time-of-flight mass spectrometry (GC x GC/TOFMS), respectively. In the GUMS analysis, serially coupled columns were used. By comparing the GUMS results with GC x GC/TOFMS result,,, many more components in the essential oil could be found within the two-dimensional separation space of GC x GC. The quantitative determination of components in the essential oil was performed by GC x GC with flame ionization detection (FID), using a method of multiple internal standards calibration, (c) 2005 Elsevier B.V. All rights reserved.
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A quantitative analysis of the individual compounds in tobacco essential oils is performed by comprehensive two-dimensional gas chromatography (GC x GC) combined with flame ionization detector (FID). A time-of-flight mass spectrometer (TOF/MS) was coupled to GC x GC for the identification of the resolved peaks. The response of a flame ionization detector to different compound classes was calibrated using multiple internal standards. In total, 172 compounds were identified with good match and 61 compounds with high probability value were reliably quantified. For comparative purposes, the essential oil sample was also quantified by one-dimensional gas chromatography-mass spectrometry (GC/MS) with multiple internal standards method. The results showed that there was close agreement between the two analysis methods when the peak purity and match quality in one-dimensional GC/MS are high enough. (c) 2005 Elsevier B.V. All rights reserved.
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Summary Background Reflective writing is a mandatory part of nurse education but how students develop their skills and use reflection as part of their experiential learning remains relatively unknown. Understanding reflective writing in all forms from the perspective of a student nurse is therefore important. Objectives To explore the use of reflective writing and the use of poetry in pre-registered nursing students. Design A qualitative design was employed to explore reflective writing in pre-registered nursing students. Setting A small university in Scotland. Participants BSc (Hons) Adult and Mental Health Pre-registration Student Nurses. Methods Two focus groups were conducted with 10 student nurses during March 2012. Data was analysed thematically using the framework of McCarthy (1999). Results Students found the process of reflective writing daunting but valued it over time. Current educational methods, such as assessing reflective accounts, often lead to the ‘narrative’ being watered down and the student feeling judged. Despite this, reflection made students feel responsible for their own learning and research on the topic. Some students felt the use of models of reflection constricting, whilst poetry freed up their expression allowing them to demonstrate the compassion for their patient under their care. Conclusions Poetry writing gives students the opportunity for freedom of expression, personal satisfaction and a closer connection with their patients, which the more formal approach to reflective writing did not offer. There is a need for students to have a safe and supportive forum in which to express and have their experiences acknowledged without the fear of being judged.
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Draper, J., Darby, R.M., Beckmann, M., Maddison, A.L., Mondhe, M., Sheldrick, C., Taylor, J., Goodacre, R., and Kell, D.B. (2002) Metabolic Engineering, metabolite profiling and machine learning to investigate the phloem-mobile signal in systemic acquired resistance in tobacco. First International Congress on Plant Metabolomics, Wageningen, The Netherlands
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Francis, Matthew, Language and Community in the Poetry of W.S. Graham (Cambridge: Salt Publishing, 2004) RAE2008
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Woods, Timothy, The Poetics of the Limit (New York: Palgrave Macmillan, 2003) RAE2008
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Woods, T. (2006). 'Preferring the wrong way': Mapping the Ethical Diversity of US Twentieth-Century Poetry. In C. Bigsby (Ed.), The Cambridge Companion to Modern American Culture (pp.450-468). Cambridge: Cambridge University Press. RAE2008
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Archer, Jayne, 'A ?Perfect Circle'? Alchemy in the Poetry of Hester Pulter', Literature Compass (2005) 2(1) pp.1-14 RAE2008
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Hughes, I. (2006). The Four Branches of the Mabinogi and Medieval Welsh Poetry. Studi Celtici. 4, pp.155-193. RAE2008