15,001 research outputs found
Maximal subgroups of sporadic groups
A systematic study of maximal subgroups of the sporadic simple groups began
in the 1960s. The work is now almost complete, only a few cases in the Monster
remaining outstanding. We give a survey of results obtained, and methods used,
over the past 50 years, for the classification of maximal subgroups of sporadic
simple groups, and their automorphism groups.Comment: To appear in Proceedings of the Princeton Conference, November 2015,
AMS Contemporary Mathematics series. Version 2 with a minor correction to the
last tabl
ciliaFA : a research tool for automated, high-throughput measurement of ciliary beat frequency using freely available software
Background: Analysis of ciliary function for assessment of patients suspected of primary ciliary dyskinesia (PCD) and
for research studies of respiratory and ependymal cilia requires assessment of both ciliary beat pattern and beat
frequency. While direct measurement of beat frequency from high-speed video recordings is the most accurate and
reproducible technique it is extremely time consuming. The aim of this study was to develop a freely available
automated method of ciliary beat frequency analysis from digital video (AVI) files that runs on open-source software
(ImageJ) coupled to Microsoft Excel, and to validate this by comparison to the direct measuring high-speed video
recordings of respiratory and ependymal cilia. These models allowed comparison to cilia beating between 3 and 52 Hz.
Methods: Digital video files of motile ciliated ependymal (frequency range 34 to 52 Hz) and respiratory epithelial cells
(frequency 3 to 18 Hz) were captured using a high-speed digital video recorder. To cover the range above between 18
and 37 Hz the frequency of ependymal cilia were slowed by the addition of the pneumococcal toxin pneumolysin.
Measurements made directly by timing a given number of individual ciliary beat cycles were compared with those
obtained using the automated ciliaFA system.
Results: The overall mean difference (± SD) between the ciliaFA and direct measurement high-speed digital imaging
methods was −0.05 ± 1.25 Hz, the correlation coefficient was shown to be 0.991 and the Bland-Altman limits of
agreement were from −1.99 to 1.49 Hz for respiratory and from −2.55 to 3.25 Hz for ependymal cilia.
Conclusions: A plugin for ImageJ was developed that extracts pixel intensities and performs fast Fourier
transformation (FFT) using Microsoft Excel. The ciliaFA software allowed automated, high throughput measurement of
respiratory and ependymal ciliary beat frequency (range 3 to 52 Hz) and avoids operator error due to selection bias. We
have included free access to the ciliaFA plugin and installation instructions in Additional file 1 accompanying this
manuscript that other researchers may use
Errata: Heat exchanger network cleaning scheduling: From optimal control to mixed-integer decision making
Errata to the article by Al Ismaili et al. [1], on the optimal scheduling of cleaning actions for Heat Exchanger Networks under fouling, are presented. Errors present in the equations of the Pontryagin Minimum Principle analysis of the original article are indicated and rectified. It is noted that despite these errors, there is no change to the conclusions of the analysis given in Al Ismaili et al. [1]
- …