67 research outputs found
Chemical, molecular pharmacology and neuroprotective properties of the essential oil derived from Aloysia citrodora Palau
Essential oils derived from dried and fresh leaves of Aloysia citrodora were obtained by hydrodistillation, and were investigated for a range of pharmacological properties: receptor binding, in vitro acetylcholinesterase (AChE) inhibitory, antioxidant activities, and neuroprotection properties relevant to neurodegenerative diseases. Fresh leaf A. citrodora essential oil inhibited [3H] nicotine binding to well washed rat forebrain membranes, with mean apparent IC50 of 0.0018 mg/ml. No significant binding activity was observed for A. citrodora essential oil derived from fresh or dried leaves, for GABAAR and NMDARs. A. citrodora essential oil, both dried and fresh, exhibited radical scavenging activity (up to 100%, IC50 < 0.0001 mg/ml) and iron (II) chelating properties (approx. IC50 = 0.05 mg/ml), and showed neuroprotective characteristics against the toxic effects of H2O2 (100%, 0.001 mg/ml) and ÎČ-amyloid (approx. 50%, 0.01 mg/ml) in CAD neuronal cell culture. Both EOs from dried and fresh leaves also displayed effective AChE inhibitory activity, with the dried leaves oil displaying more clear AChE inhibitory activity than fresh oil, which could be related to the higher respective levels of caryophyllene oxide. Recombinant human anticholinesterase enzyme was used for structure based in silico screening of A. citrodora essential oil constituents for AChE Inhibitors, and the top scoring hits with highest pharmacophore fit values showed common interactions with residues at the active site of that of donepezil. The top seven hits in order of fit score, were ÎČ-curcumene, curcumene bisabolene, trans-calamenene, caryophyllene oxide, ÎČ-sesquiphellandrene and geranyl acetate. This indicates that plants may yield novel effective and safe AChE inhibitors, other than alkaloids. To begin to identify the chemicals underpinning the pharmacological properties of A. citrodora, GC/MS analysis of the chemical composition of the essential oil from leaves of A. citrodora identified eighty three major chemicals, including the presence of terpenoids, monoterpenes and sesquiterpenes, and 6-methyl-5-hepten-2-one, the main constituents being limonene, caryophyllene oxide, curcumene, spathulenol, 1,8-cineole constituting 47% of the total oil. Finally, a simple, inexpensive solid phase extraction method was developed for fractionation of essential oils. Collectively, this thesis provides a better understanding of the pharmacology of the Aloysia essential oil and its constituents relating to its potential use in the treatment neurodegenerative disease
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Writ(h)ing Images: Imagination, the Human Form, and the Divine in William Blake, Salman Rushdie, and Simon Louvish
In this paper, we address issues in segmentation Of remotely sensed LIDAR (LIght Detection And Ranging) data. The LIDAR data, which were captured by airborne laser scanner, contain 2.5 dimensional (2.5D) terrain surface height information, e.g. houses, vegetation, flat field, river, basin, etc. Our aim in this paper is to segment ground (flat field)from non-ground (houses and high vegetation) in hilly urban areas. By projecting the 2.5D data onto a surface, we obtain a texture map as a grey-level image. Based on the image, Gabor wavelet filters are applied to generate Gabor wavelet features. These features are then grouped into various windows. Among these windows, a combination of their first and second order of statistics is used as a measure to determine the surface properties. The test results have shown that ground areas can successfully be segmented from LIDAR data. Most buildings and high vegetation can be detected. In addition, Gabor wavelet transform can partially remove hill or slope effects in the original data by tuning Gabor parameters
'Vernacular Voices: Black British Poetry'
ABSTRACT
Black British poetry is the province of experimenting with voice and recording rhythms beyond the iambic pentameter. Not only in performance poetry and through the spoken word, but also on the page, black British poetry constitutes and preserves a sound archive of distinct linguistic varieties. In Slave Song (1984) and Coolie Odyssey (1988), David Dabydeen employs a form of Guyanese Creole in order to linguistically render and thus commemorate the experience of slaves and indentured labourers, respectively, with the earlier collection providing annotated translations into Standard English. James Berry, Louise Bennett, and Valerie Bloom adapt Jamaican Patois to celebrate Jamaican folk culture and at times to represent and record experiences and linguistic interactions in the postcolonial metropolis. Grace Nichols and John Agard use modified forms of Guyanese Creole, with Nichols frequently constructing gendered voices whilst Agard often celebrates linguistic playfulness. The borders between linguistic varieties are by no means absolute or static, as the emergence and marked growth of âLondon Jamaicanâ (Mark Sebba) indicates. Asian British writer Daljit Nagra takes liberties with English for different reasons. Rather than having recourse to established Creole languages, and blending them with Standard English, his heteroglot poems frequently emulate âPunglishâ, the English of migrants whose first language is Punjabi. Whilst it is the language prestige of London Jamaican that has been significantly enhanced since the 1990s, a fact not only confirmed by linguistic research but also by its transethnic uses both in the streets and on the page, Nagraâs substantial success and the mainstream attention he receives also indicate the clout of vernacular voices in poetry. They have the potential to connect with oral traditions and cultural memories, to record linguistic varieties, and to endow âstreet credâ to authors and texts. In this chapter, these double-voiced poetic languages are also read as signs of resistance against residual monologic ideologies of Englishness.
© Book proposal (02/2016): The Cambridge History of Black and Asian British Writing p. 27 of 4
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Forging connections: anthologies, arts collectives, and the politics of inclusion
The changing social and political landscape of twentieth-century Britain catalysed a remarkable rise in collaborative activity by artists and activists of black and Asian heritage. Creative communities began to gather in both local and regional contexts, with the aim of sharing resources and securing an audience. This chapter records some of these many activities, tracing the groupsâ genesis, manifest objectives, and key contributions. It argues that anthologising should be understood as a specifically motivated activity. Literary anthologies of poetry and fiction served to showcase the diversity of contemporary writing, while also suggesting its coherence. Drawing on the concept of âstrategic essentialismâ elucidated by Gayatri Chakravorty Spivak, I show that the anthology acts to ensure the visibility of a group, bannered as a unified and singly-titled selection of texts, while also insisting on the differences within: the heterogeneous multiplicity of black and Asian British experiences and creative practices
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