178 research outputs found

    Position Measurements with Micro-Channel Plates and Transmission lines using Pico-second Timing and Waveform Analysis

    Get PDF
    The anodes of Micro-Channel Plate devices are coupled to fast transmission lines in order to reduce the number of electronics readout channels, and can provide two-dimension position measurements using two-ends delay timing. Tests with a laser and digital waveform analysis show that resolutions of a few hundreds of microns along the transmission line can be reached taking advantage of a few pico-second timing estimation. This technique is planned to be used in Micro-channel Plate devices integrating the transmission lines as anodes

    Single-cell whole-genome amplification technique impacts the accuracy of SNP microarray-based genotyping and copy number analyses

    Get PDF
    Methods of comprehensive microarray-based aneuploidy screening in single cells are rapidly emerging. Whole-genome amplification (WGA) remains a critical component for these methods to be successful. A number of commercially available WGA kits have been independently utilized in previous single-cell microarray studies. However, direct comparison of their performance on single cells has not been conducted. The present study demonstrates that among previously published methods, a single-cell GenomePlex WGA protocol provides the best combination of speed and accuracy for single nucleotide polymorphism microarray-based copy number (CN) analysis when compared with a REPLI-g- or GenomiPhi-based protocol. Alternatively, for applications that do not have constraints on turnaround time and that are directed at accurate genotyping rather than CN assignments, a REPLI-g-based protocol may provide the best solution

    Reynolds Number Effects at High Angles of Attack

    Get PDF
    Lessons learned from comparisons between ground-based tests and flight measurements for the high-angle-of-attack programs on the F-18 High Alpha Research Vehicle (HARV), the X-29 forward-swept wing aircraft, and the X-31 enhanced fighter maneuverability aircraft are presented. On all three vehicles, Reynolds number effects were evident on the forebodies at high angles of attack. The correlation between flight and wind tunnel forebody pressure distributions for the F-18 HARV were improved by using twin longitudinal grit strips on the forebody of the wind-tunnel model. Pressure distributions obtained on the X-29 wind-tunnel model at flight Reynolds numbers showed excellent correlation with the flight data up to alpha = 50 deg. Above (alpha = 50 deg. the pressure distributions for both flight and wind tunnel became asymmetric and showed poorer agreement, possibly because of the different surface finish of the model and aircraft. The detrimental effect of a very sharp nose apex was demonstrated on the X-31 aircraft. Grit strips on the forebody of the X-31 reduced the randomness but increased the magnitude of the asymmetry. Nose strakes were required to reduce the forebody yawing moment asymmetries and the grit strips on the flight test noseboom improved the aircraft handling qualities

    The scene of the crime: inventing the serial killer

    Get PDF
    This article examines the meanings of the crime scene in serial killings, and the tensions between the real and the imagined in the circulation of those meanings. Starting with the Whitechapel Murders of 1888 it argues that they, as well as forming an origin for the construction of the identity of 'the serial killer', initiate certain ideas about the relationship of subjects to spaces and the existence of the self in the modern urban landscape. It suggests that these ideas come to play an integral part in the contemporary discourse of serial killing, both in the popular imagination and in professional analysis. Examining the Whitechapel Murders, more recent cases and modern profiling techniques, it argues that popular and professional representations of crime scenes reveal more of social anxieties about the nature of the public and the private than they do about serial killers. It suggests that 'the serial killer' is not a coherent type, but an invention produced from the confusions of persons and places. Copyright 2006 SAGE Publications. All rights reserved. Not for commercial use or unauthorized distribution

    Methods for comprehensive chromosome screening of oocytes and embryos: capabilities, limitations, and evidence of validity

    Get PDF
    Preimplantation aneuploidy screening of cleavage stage embryos using fluorescence in situ hybridization (FISH) may no longer be considered the standard of care in reproductive medicine. Over the last few years, there has been considerable development of novel technologies for comprehensive chromosome screening (CCS) of the human genome. Among the notable methodologies that have been incorporated are whole genome amplification, metaphase and array based comparative genomic hybridization, single nucleotide polymorphism microarrays, and quantitative real-time PCR. As these methods become more integral to treating patients with infertility, it is critical that clinicians and scientists obtain a better understanding of their capabilities and limitations. This article will focus on reviewing these technologies and the evidence of their validity
    corecore