67 research outputs found
Improving feature selection algorithms using normalised feature histograms
The proposed feature selection method builds a histogram of the most stable
features from random subsets of a training set and ranks the features based on
a classifier based cross-validation. This approach reduces the instability of
features obtained by conventional feature selection methods that occur with
variation in training data and selection criteria. Classification results on
four microarray and three image datasets using three major feature selection
criteria and a naive Bayes classifier show considerable improvement over
benchmark results
Quantum Hall activation gaps in bilayer graphene
We have measured the quantum Hall activation gaps in bilayer graphene at
filling factors and in high magnetic fields up to 30 T.
We find that energy levels can be described by a 4-band relativistic hyperbolic
dispersion. The Landau level width is found to contain a field independent
background due to an intrinsic level broadening and a component which increases
linearly with magnetic field.Comment: 4 pages, accepted version (just removed a few typos), will appear as
Fast Track Communication in Solid State Commu
Global transcriptional response of Saccharomyces cerevisiae to the deletion of SDH3
<p>Abstract</p> <p>Background</p> <p>Mitochondrial respiration is an important and widely conserved cellular function in eukaryotic cells. The succinate dehydrogenase complex (Sdhp) plays an important role in respiration as it connects the mitochondrial respiratory chain to the tricarboxylic acid (TCA) cycle where it catalyzes the oxidation of succinate to fumarate. Cellular response to the Sdhp dysfunction (i.e. impaired respiration) thus has important implications not only for biotechnological applications but also for understanding cellular physiology underlying metabolic diseases such as diabetes. We therefore explored the physiological and transcriptional response of <it>Saccharomyces cerevisiae </it>to the deletion of <it>SDH3</it>, that codes for an essential subunit of the Sdhp.</p> <p>Results</p> <p>Although the Sdhp has no direct role in transcriptional regulation and the flux through the corresponding reaction under the studied conditions is very low, deletion of <it>SDH3 </it>resulted in significant changes in the expression of several genes involved in various cellular processes ranging from metabolism to the cell-cycle. By using various bioinformatics tools we explored the organization of these transcriptional changes in the metabolic and other cellular functional interaction networks.</p> <p>Conclusion</p> <p>Our results show that the transcriptional regulatory response resulting from the impaired respiratory function is linked to several different parts of the metabolism, including fatty acid and sterol metabolism.</p
Evaluation of oxidative stress in brucella infected cows
Oxidative stress can influence the metabolism of cells in vital organs of the body. Oxidative stress is extremely dangerous as it does not exhibit any symptom and is recognisable with great difficulty by means of laboratory methods. It can be monitored with several biomarkers like antioxidants and pro-oxidants which can be assessed in serum. The inexorableness of exposure of cows to brucella infection makes oxidative stress associated with this infection an appropriate field of investigation. There is paucity of work to detect stress, which is essential to take timely corrective measures and to save the animal population. Therefore the investigation was carried out to evaluate oxidative stress in the cows suffering from brucellosis. For this serum iomarkers of oxidative stress viz. vitamin C, vitamin E, catalase, monoamine oxidase, glutathione reductase, superoxide dismutase, glutathione, xanthine oxidase, oxidase and peroxidase were determined. Results indicated that vitamin C, vitamin E and glutathione activity decreased significantly in affected cows as compared to healthy cows. Serum catalase, superoxide dismutase, monoamine oxidase, glutathione reductase, xanthine oxidase, oxidase and peroxidase activities increased significantly in affected cows as compared to healthy cows. Decreased activity of vitamin C, vitamin E and glutathione indicated towards their depletion which generally occurs in the oxidative stress to scavenge the free radicals. It was concluded that oxidative stress was there in the animals. This study recommends the use of antioxidants in affected cow
Improved conductance quantization in gold point contacts in high magnetic fields
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Scattering of ballistic electrons at a mesoscopic spot of strong magnetic field
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115632.pdf (publisher's version ) (Open Access)4 p
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