Relative categories: Another model for the homotopy theory of homotopy theories

We lift Charles Rezk's complete Segal space model structure on the category of simplicial spaces to a Quillen equivalent one on the category of relative categories.Comment: 27 pages. Updated to correct typographical error

Charge Determination of High Energy Electrons and Nuclei by Synchrotron Radiation with AMS

We investigate the possibilities to identify the charge of TeV electrons and PeV nuclei using their synchrotron radiation in the earth's magnetic field. Characteristics of synchrotron radiation photons are evaluated and methods of detection are discussed.Comment: 9 pages, 6 figure

A characterization of simplicial localization functors

We characterize simplicial localization functors among relative functors from relative categories to simplicial categories as any choice of homotopy inverse to the delocalization functor of Dwyer and the second author.Comment: 7 pages. Typographical errors correcte

n-relative categories: a model for the homotopy theory of n-fold homotopy theories

We introduce, for every integer n ≥ 1, the notion of an n-relative category and show that the category of the small n-relative categories is a model for the homotopy theory of n-fold homotopy theories, i.e., homotopy theories of… homotopy theories

In Support of the Care Bill: The Needs for Federally Mandated Minimum Education Standards in Diagnostic Medical Sonography

It is erroneously assumed that qualified professionals are performing diagnostic medical ultrasound procedures in medical facilities throughout the United States. To address this issue, the CARE bill has been proposed to the federal legislature. The bill’s primary intent is to mandate that medical facilities being reimbursed by the federal government for such diagnostic procedures comply with a minimum educational and training standard. Enactment of this legislation will create the need to provide the mandated education and training to a currently unknown number of individuals in a manner that is acceptable to standards compliance, as well as the employer and employee. A nationwide survey to identify demographics and educational backgrounds of this group as well as their employer’s perceptions related to necessary employee training/retraining is recommended

An experiment to measure the energy spectrum of cosmic ray antiprotons from 100 to 1000 MeV

Production models were developed and the confirmation of each one had significant astrophysical impact. These include radical modifications of propagation models, cosmic ray antiprotons injection from neighboring domains of antimatter, p production by evaporating primordial black holes, and cosmic ray p's as annihilation products of supersymmetry particles that might make up the dark dynamical mass of the Galaxy. It is that p's originating from supersymmetric parents might have distinct spectral features that would survive solar modulation; in one model, higgsino annihilation proceeds through the bb quark-antiquark channel, producing a spectral bump at approx. 0.3 GeV in the p spectrum