1,559 research outputs found
Performance evaluation of a prudent two-phase commit protocol
Studies a prudent two-phase commit protocol, which in the presence of failures does not abort a transaction carelessly. Thus system performance is improved
VennDiagramWeb: a web application for the generation of highly customizable Venn and Euler diagrams.
BackgroundVisualization of data generated by high-throughput, high-dimensionality experiments is rapidly becoming a rate-limiting step in computational biology. There is an ongoing need to quickly develop high-quality visualizations that can be easily customized or incorporated into automated pipelines. This often requires an interface for manual plot modification, rapid cycles of tweaking visualization parameters, and the generation of graphics code. To facilitate this process for the generation of highly-customizable, high-resolution Venn and Euler diagrams, we introduce VennDiagramWeb: a web application for the widely used VennDiagram R package. VennDiagramWeb is hosted at http://venndiagram.res.oicr.on.ca/ .ResultsVennDiagramWeb allows real-time modification of Venn and Euler diagrams, with parameter setting through a web interface and immediate visualization of results. It allows customization of essentially all aspects of figures, but also supports integration into computational pipelines via download of R code. Users can upload data and download figures in a range of formats, and there is exhaustive support documentation.ConclusionsVennDiagramWeb allows the easy creation of Venn and Euler diagrams for computational biologists, and indeed many other fields. Its ability to support real-time graphics changes that are linked to downloadable code that can be integrated into automated pipelines will greatly facilitate the improved visualization of complex datasets. For application support please contact [email protected]
Application of the group-theoretical method to physical problems
The concept of the theory of continuous groups of transformations has
attracted the attention of applied mathematicians and engineers to solve many
physical problems in the engineering sciences. Three applications are presented
in this paper. The first one is the problem of time-dependent vertical
temperature distribution in a stagnant lake. Two cases have been considered for
the forms of the water parameters, namely water density and thermal
conductivity. The second application is the unsteady free-convective
boundary-layer flow on a non-isothermal vertical flat plate. The third
application is the study of the dispersion of gaseous pollutants in the
presence of a temperature inversion. The results are found in closed form and
the effect of parameters are discussed
Low-Temperature Growth of High Resistivity GaAs by Photoassisted Metalorganic Chemical Vapor Deposition
We report the photoassisted lowâtemperature (LT) metalorganic chemical vapor deposition (MOCVD) of high resistivity GaAs. The undoped asâgrown GaAs exhibits a resistivity of âŒ106 Ωâcm, which is the highest reported for undoped material grown in the MOCVD environment. Photoassisted growth of doped and undoped device quality GaAs has been achieved at a substrate temperature of 400â°C in a modified atmospheric pressure MOCVD reactor. By using silane as a dopant gas, the LT photoassisted doped films have high levels of doping and electron mobilities comparable to those achieved by MOCVD for growth temperatures, Tgâł600â°C
Capacitanceâvoltage characterization of AlN/GaN metalâinsulatorâsemiconductor structures grown on sapphire substrate by metalorganic chemical vapor deposition
Electrical characterization of AlN/GaN interfaces was carried out by the capacitanceâvoltage (CâV)(CâV) technique in materials grown by metalorganic chemical vapor deposition. The high-frequency CâVCâV characteristics showed clear deep-depletion behavior at room temperature, and the doping density derived from the slope of 1/C21/C2 plots under the deep depletion condition agreed well with the growth design parameters. A low value of interface state density DitDit of 1Ă1011âcmâ2âeVâ11Ă1011âcmâ2âeVâ1 or less around the energy position of Ecâ0.8âeVEcâ0.8âeV was demonstrated, in agreement with an average DitDit value estimated from photoassisted CâVCâV characteristics. © 2000 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70376/2/JAPIAU-88-4-1983-1.pd
Ensemble analyses improve signatures of tumour hypoxia and reveal inter-platform differences
BACKGROUND: The reproducibility of transcriptomic biomarkers across datasets remains poor, limiting clinical application. We and others have suggested that this is in-part caused by differential error-structure between datasets, and their incomplete removal by pre-processing algorithms. METHODS: To test this hypothesis, we systematically assessed the effects of pre-processing on biomarker classification using 24 different pre-processing methods and 15 distinct signatures of tumour hypoxia in 10 datasets (2,143 patients). RESULTS: We confirm strong pre-processing effects for all datasets and signatures, and find that these differ between microarray versions. Importantly, exploiting different pre-processing techniques in an ensemble technique improved classification for a majority of signatures. CONCLUSIONS: Assessing biomarkers using an ensemble of pre-processing techniques shows clear value across multiple diseases, datasets and biomarkers. Importantly, ensemble classification improves biomarkers with initially good results but does not result in spuriously improved performance for poor biomarkers. While further research is required, this approach has the potential to become a standard for transcriptomic biomarkers
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