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Abstract : Isolation of a New Steroidal Glycoalkaloid from Solanum xanthocarpum
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Abstract: A new steroidal glycoalkaloid was isolated from barries of Solanum xanthocarpum, together with two other known steroidal glycoalkaloids. The structure of new steroidal glycoalkaloid was elucidated as O-(3){ α-L- rhamnopyranosyl-(1→2gal)- β-D- galactopyranosyl}-solasodine on the basis of spectroscopic analysis as well as comparison with reported spectroscopic data of related compounds. Keywords: Solanum xanthocarpum, steroidal glycoalkaloid, O-(3) {α-L-rhamnopyranosyl-(1→2gal)-β-D- galactopyranosyl}-solasodine.Download Full Article |
Abstract : Reformulation of Adams-Moulton Block Methods as a Sub-Class of Two Step Runge-Kutta Method
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Abstract: Adams-Moulton methods for k = 2 and k = 3 were constructed together with their continuous forms using multi-step collocation methods. The continuous forms were then evaluated at various grid points to produce the block Adams-Moulton methods. The block methods were then reformulated as a sub-class of two step Runge-Kutta methods (TSRK). Both the Adams and the reformulated methods were applied to solve initial value problems and the reformulated methods proved superior in terms of stability. Keywords: Reformulation, Adams-Moulton, block method, two-step, Runge-Kutta and collocation.Download Full Article |
Abstract : PB1-F2 Amino Acids Regulate Influenza A Viral Polymerase Activity
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Abstract: In 2001, the 11th influenza A viral protein PB1-F2 was detected and found to be encoded by an alternative open reading frame in the PB1 polymerase gene. PB1-F2 has several unique functions, including roles in promoting apoptosis, increasing inflammation, and regulating viral polymerase activity. This study focused on a single PB1-F2 function: regulation of polymerase activity. We constructed a minigenome system to determine the influence of PB1-F2 amino acid (aa) mutations on polymerase activity. We examined four types of aa mutations: three species-specific aa mutations and one mutation that alters pathogenicity in mice. We discovered that an arginine (R) residue at aa position 29 is highly conserved in avian-derived virus strains. Introducing this mutation into mammalian strain A/WSN/33 (H1N1) led to a marked increase in polymerase activity in mammalian cells.These findings suggest that as PB1-F2 in H5N1 viruses regulates viral polymerase activity, it could be targeted for control of avian influenza infection and drug discovery. Keywords: Influenza A virus, PB1-F2, polymerase activity, minigenome system.Download Full Article |
Abstract : Socio-Agricultural Correlation and Regionalization: A Case of the Districts of Pakistan
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Abstract: The main economic activity of a large segment of population in Pakistan is agriculture. The contrasting pattern of topography and uneven distribution of resources create a wide difference in socio-agricultural relationship among the different administrative districts of the country. The study aims to investigate the correlation based on a number of variables extracted from different sectors of Pakistan’s agriculture and social infrastructure. In order to study the regionalization multivariate analysis has been done for hundred districts of Pakistan. The results produced, show sharp variation of regional disparity among the different districts of Pakistan. A clear cut longitudinal east-west divide is visible from the outcome of the study. The provinces of Punjab and Sindh, consisting of fertile plains of river Indus and its tributaries stand out with better socio-agricultural correlation. The western provinces of Khyber Pakhtoonkhwa and Balochistan, surrounded by mountains and plateau depict a deprived scene in terms of socio-agricultural well-being. In Pakistan districts are very vital for resource planning and development. These administrative units have a mix of both rural and urban activities that is why this study becomes more significant for future district planning decisions. Keywords: Multivariate analysis, planning and development, regionalization, socio-agriculture relationship, uneven distribution.Download Full Article |
