47,556 research outputs found

    A Virtual Pandora\u27s Box: What Cyberspace Gambling Prohibition Means to Terrestrial Casino Operators

    Full text link
    Recently, there has been increased pressure on the U.S. Congress to act against Internet gambling. While it may be tempting for terrestrial casinos to watch idly as the federal government moves to eliminate a potential competitor, those in the business of gaming must be leery of any federal efforts to halt gambling online. In the final analysis, the same arguments to restrict consumer choice in cyberspace can be easily used against gambling in real casinos-a compelling reason for terrestrial gaming operators to forcefully oppose any federal restrictions on Americans\u27 rights to gamble

    Tribute - David G. Schwartz

    Full text link

    A theory for the interpretation of lunar surface magnetometer data

    Get PDF
    Electromagnetic interaction of moon with spatial irregularities in interplanetary magnetic field

    The early despinning of the sun

    Get PDF
    Despinning of sun when passing through T Tauri stage during earlier developmen

    Transient electromagnetic interaction of the moon with the solar wind

    Get PDF
    Transient response of moon to variations in interplanetary magnetic fiel

    A medieval fallacy: the crystalline lens in the center of the eye.

    Get PDF
    ObjectiveTo determine whether, as most modern historians have written, ancient Greco-Roman authors believed the crystalline lens is positioned in the center of the eye.BackgroundHistorians have written that statements about cataract couching by Celsus, or perhaps Galen of Pergamon, suggested a centrally located lens. Celsus specifically wrote that a couching needle placed intermediate between the corneal limbus and the lateral canthus enters an empty space, presumed to represent the posterior chamber.MethodsAncient ophthalmic literature was analyzed to understand where these authors believed the crystalline lens was positioned. In order to estimate where Celsus proposed entering the eye during couching, we prospectively measured the distance from the temporal corneal limbus to the lateral canthus in 30 healthy adults.ResultsRufus of Ephesus and Galen wrote that the lens is anterior enough to contact the iris. Galen wrote that the lens equator joins other ocular structures at the corneoscleral junction. In 30 subjects, half the distance from the temporal corneal limbus to the lateral canthus was a mean of 4.5 mm (range: 3.3-5.3 mm). Descriptions of couching by Celsus and others are consistent with pars plana entry of the couching needle. Anterior angulation of the needle would permit contact of the needle with the lens.ConclusionAncient descriptions of anatomy and couching do not establish the microanatomic relationships of the ciliary region with any modern degree of accuracy. Nonetheless, ancient authors, such as Galen and Rufus, clearly understood that the lens is located anteriorly. There is little reason to believe that Celsus or other ancient authors held a variant understanding of the anatomy of a healthy eye. The notion of the central location of the lens seems to have arisen with Arabic authors in 9th century Mesopotamia, and lasted for over 7 centuries

    Quark and Gluon Tagging at the LHC

    Get PDF
    Being able to distinguish light-quark jets from gluon jets on an event-by-event basis could significantly enhance the reach for many new physics searches at the Large Hadron Collider. Through an exhaustive search of existing and novel jet substructure observables, we find that a multivariate approach can filter out over 95% of the gluon jets while keeping more than half of the light-quark jets. Moreover, a combination of two simple variables, the charge track multiplicity and the pTp_T-weighted linear radial moment (girth), can achieve similar results. While this pair appears very promising, our study is only Monte Carlo based, and other discriminants may work better with real data in a realistic experimental environment. To that end, we explore many other observables constructed using different jet sizes and parameters, and highlight those that deserve further theoretical and experimental scrutiny. Additional information, including distributions of around 10,000 variables, can be found on this website http://jets.physics.harvard.edu/qvg .Comment: 5 pages, 3 figures. v2 published versio
    • …
    corecore