719 research outputs found

    Moly: a prototype handheld three-dimensional digitizer with diffraction optics

    Get PDF
    A working handheld 3-D diffraction range finder, nicknamed Moly, is demonstrated. This prototype is distinguished by a far-field magnification feature that is made possible by use of chirped frequency diffraction grating optics that reverse the perspective foreshortening typical of conventional triangulation range finders. This new type of 3-D profilometer illuminates its target with a collimated laser projector that produces a rectangle-shaped sheet of light of uniform width at all working distances. Moly also employs dual magnetic wave detectors to facilitate freedom of movement for both the digitizing instrument and the subject. The instrument was designed primarily to digitize human faces and figures for applications in art and medicine

    Rooftop and indoor reception with transmit diversity applied to DVB-T networks: A long term measurement campaign

    Get PDF
    Although transmit Delay Diversity (DD) can provide a gain in indoor and other Non Line of Sight situations (NLOS), it can introduce degradation in rooftop reception. In fact, when the Ricean K factor of the channel is significantly high (e.g. Line of Sight reception), the channel performs similar to an AWGN channel where the performance degrades due to DD that artificially increase the fading. This paper investigates through practical evaluation the impacts of Transmit DD on LOS and NLOS stationary reception. Then, it studies 2 techniques to reduce the degradation performance in LOS while aiming to keep the same diversity gain in NLOS receptio

    Skin prick testing does not reflect the presence of IgE against food allergens in adult eosinophilic esophagitis patients: a case study

    Get PDF
    Skin prick testing is widely used to predict the presence of allergen-specific IgE. In eosinophilic esophagitis patients, who frequently exhibit polysensitization and broad reactivity upon skin prick testing, this is commonly used to aid avoidance recommendations in the clinical management of their disease. We present here the predictive value of skin prick testing for the presence of allergen-specific IgE, in 12 patients, determined by immunoblot against the allergen extracts using individual-matched serum. Our results demonstrate a high degree of predictive value for aeroallergens but a poor predictive value for food allergens. This suggests that skin prick testing likely identifies IgE reactivity towards aeroallergens in adult eosinophilic esophagitis but this is not true for foods. Consequently, IgE immunoblotting might be required for determining food avoidance in these patients

    Pulsation period variations in the RRc Lyrae star KIC 5520878

    Full text link
    Learned et. al. proposed that a sufficiently advanced extra-terrestrial civilization may tickle Cepheid and RR Lyrae variable stars with a neutrino beam at the right time, thus causing them to trigger early and jogging the otherwise very regular phase of their expansion and contraction. This would turn these stars into beacons to transmit information throughout the galaxy and beyond. The idea is to search for signs of phase modulation (in the regime of short pulse duration) and patterns, which could be indicative of intentional, omnidirectional signaling. We have performed such a search among variable stars using photometric data from the Kepler space telescope. In the RRc Lyrae star KIC 5520878, we have found two such regimes of long and short pulse durations. The sequence of period lengths, expressed as time series data, is strongly auto correlated, with correlation coefficients of prime numbers being significantly higher (p=99.8p=99.8\%). Our analysis of this candidate star shows that the prime number oddity originates from two simultaneous pulsation periods and is likely of natural origin. Simple physical models elucidate the frequency content and asymmetries of the KIC 5520878 light curve. Despite this SETI null result, we encourage testing other archival and future time-series photometry for signs of modulated stars. This can be done as a by-product to the standard analysis, and even partly automated.Comment: Accepted for publication in ApJ. 49 pages, 16 figure

    Studying the Psychological Impacts of the COVID-19 Pandemic on Frontline Healthcare Workers

    Get PDF
    Purpose: The purpose of this study was to determine the prevalence of psychological distress in frontline healthcare workers during the COVID 19 pandemic, and to identify if interventions and higher measures of resiliency helped to minimize the prevalence of symptoms.https://scholarlycommons.henryford.com/nursresconf2021/1002/thumbnail.jp

    Chaogates: morphing logic gates that exploit dynamical patterns

    Get PDF
    Chaotic systems can yield a wide variety of patterns. Here we use this feature to generate all possible fundamental logic gate functions. This forms the basis of the design of a dynamical computing device, a chaogate, that can be rapidly morphed to become any desired logic gate. Here we review the basic concepts underlying this and present an extension of the formalism to include asymmetric logic functions
    • …
    corecore