An analytical model of prominence dynamics

Solar prominences are magnetic structures incarcerating cool and dense gas in an otherwise hot solar corona. Prominences can be categorized as quiescent and active. Their origin and the presence of cool gas (~$10^4$K) within the hot (~$10^6$K) solar corona remains poorly understood. The structure and dynamics of solar prominences was investigated in a large number of observational and theoretical (both analytical and numerical) studies. In this paper, an analytic model of quiescent solar prominence is developed and used to demonstrate that the prominence velocity increases exponentially, which means that some gas falls downward towards the solar surface, and that Alfven waves are naturally present in the solar prominences. These theoretical predictions are consistent with the current observational data of solar quiescent prominences.Comment: Update Final Journal Print Version along with other Metadat

Approximate Data Mining Using Sketches for Massive Data

AbstractWith the popularity of the Web and Internet, massive data is generated.However, this enormous datasets present the challenge to apply data mining techniques in order to extract useful information. Dimensionality reduction can be used to improve both efficiency and effectiveness while extracting information from data. In this paper we have proposed an algorithm to reduce the dimensionality of the datasets such that after applying data mining techniques on reduced datasets we get almost same results as with the original datasets. Random Sketch is used to reduce the dimensions of the dataset

Mechanism of protonophores-mediated induction of heat-shock response in Escherichia coli

<p>Abstract</p> <p>Background</p> <p>Protonophores are the agents that dissipate the proton-motive-force (PMF) across <it>E. coli </it>plasma membrane. As the PMF is known to be an energy source for the translocation of membrane and periplasmic proteins after their initial syntheses in cell cytoplasm, protonophores therefore inhibit the translocation phenomenon. In addition, protonophores also induce heat-shock-like stress response in <it>E. coli </it>cell. In this study, our motivation was to investigate that how the protonophores-mediated phenomena like inhibition of protein translocation and induction of heat-shock proteins in <it>E. coli </it>were correlated.</p> <p>Results</p> <p>Induction of heat-shock-like response in <it>E. coli </it>attained the maximum level after about 20 minutes of cell growth in the presence of a protonophore like carbonyl cyanide m-chloro phenylhydrazone (CCCP) or 2, 4-dinitrophenol (DNP). With induction, cellular level of the heat-shock regulator protein sigma-32 also increased. The increase in sigma-32 level was resulted solely from its stabilization, not from its increased synthesis. On the other hand, the protonophores inhibited the translocation of the periplasmic protein alkaline phosphatase (AP), resulting its accumulation in cell cytosol partly in aggregated and partly in dispersed form. On further cell growth, after withdrawal of the protonophores, the previously accumulated AP could not be translocated out; instead the AP-aggregate had been degraded perhaps by an induced heat-shock protease ClpP. Moreover, the non-translocated AP formed binary complex with the induced heat-shock chaperone DnaK and the excess cellular concentration of DnaK disallowed the induction of heat-shock response by the protonophores.</p> <p>Conclusion</p> <p>Our experimental results suggested that the protonophores-mediated accumulation and aggregation of membrane proteins (like AP) in cell cytosol had signaled the induction of heat-shock proteins in <it>E. coli </it>and the non-translocated protein aggregates were possibly degraded by an induced heat-shock protease ClpP. Moreover, the induction of heat-shock response occurred by the stabilization of sigma-32. As, normally the DnaK-bound sigma-32 was known to be degraded by the heat-shock protease FtsH, our experimental results further suggested that the engagement of DnaK with the non-translocated proteins (like AP) had made the sigma-32 free and stable.</p

Geospatial analysis of the effects of tsunami on coral and mangrove ecosystems of Mayabunder in Andaman Islands, India

Mangroves and coral reefs are among the major ecosystems of tropical and subtropical coastlines. The Andaman group of islands, situated at the juncture of Bay of Bengal and Indian Ocean, are one of the richest coastal ecosystems of India in terms of biodiversity. Since the tsunami waves of 2004 affected this region severely, the outer fringes as well as inland areas of these islands faced extensive ecological degradation. Mayabunder is one such place of this region, where corals and mangroves had experienced both natural and anthropogenic threat. Considering the notable vulnerability of this coastal environment, the present study aimed to assess the transformations of the coral and mangrove ecosystems at Mayabunder both in pre-tsunami and post-tsunami periods till the present year using multi-temporal satellite imageries and geospatial techniques. Results showed that the areal coverage of healthy living coral reefs was reduced by 466.56 ha (10.42 %) from 1990 to 2000. Afterwards, the coupled ecosystem had experienced serious degradation again during the 2000−2010 phase. The areal coverage of dense mangroves decreased by 47.37%, whereas the area of dead coral covers showed a significant rise of 55.52%. However, partial restoration of both mangroves as well as healthy corals had also been observed here in recent years. It was raised from the extensive field visits and feedbacks from local inhabitants that this restoration initiative could become more effective if a participatory mode of management is adopted

ANTIBACTERIAL ACTIVITY OF METHANOL EXTRACT OF ALPINIA CONCHIGERA GRIFF (FAMILY: ZINGIBERACEAE)

oai:ojs.www.ajphsci.com:article/15The antibacterial activity of the methanol extract of Alpinia conchigera Griff was evaluated by the disc diffusion method against eleven pathogenic bacteria using ciprofloxacin as standards. In the screening, the methanol extract of Alpinia conchigera Griff showed varying degrees of antibacterial activitiy with zone of inhibition ranging from 8.0-24.5 mm, while the highest antibacterial activity was seen against with Vibrio cholerae, Staphylococcus aureus, Salmonella typhi &amp; Salmonella paratyphi.The Minimum Inhibitory Concentrations of the methanol extracts was found to be 31.25-125 μg/ml for bacteria species used in the screening.

Data on mass spectrometry based identification of allergens from sunflower (Helianthus annuus L.) pollen proteome

AbstractAllergy is a type of abnormal immune reactions, which is triggered by environmental antigens or allergens and mediated by IgE antibodies. Now-a-days mass spectrometry is the method of choice for allergen identification based on homology searching. Here, we provide the mass spectrometry dataset associated with our previously published research article on identification of sunflower pollen allergens (Ghosh et al., 2015 [1]). In this study allergenicity of sunflower (Helianthus annuus) pollen grains were primarily investigated by clinical studies followed by detailed immunobiochemical and immunoproteomic analyses. The mass spectrometry data for the identification of allergens were deposited to ProteomeXchange Consortium via PRIDE partner repository with the dataset identifier http://www.ebi.ac.uk/pride/archive/projects/PXD002397