Inside Duke University Hospital System’s Charity Care Program: Effectiveness in Serving North Carolina’s Uninsured, Undocumented, Low-Income Hispanic Families

Public Policy Honors Thesi

An exposure assessment of radionuclide emissions associated with potential mixed-low level waste disposal facilities at fifteen DOE sites

A screening method was developed to compare the doses received via the atmospheric pathway at 15 potential DOE MLLW (mixed low-level waste) sites. Permissible waste concentrations were back calculated using the radioactivity NESHAP (National Emissions Standards for Hazardous Air Pollutants) in 40 FR 61 (DOE Order 5820.2A performance objective). Site-specific soil and meteorological data were used to determine permissible waste concentrations (PORK). For a particular radionuclide, perks for each site do not vary by more than one order of magnitude. perks of {sup 14}C are about six orders of magnitude more restrictive than perks of {sup 3}H because of differences in liquid/vapor partitioning, decay, and exposure dose. When comparing results from the atmospheric pathway to the water and intruder pathways, {sup 14}C disposal concentrations were limited by the atmospheric pathway for most arid sites; for {sup 3}H, the atmospheric pathway was not limiting at any of the sites. Results of this performance evaluation process are to be used for planning for siting of disposal facilities

A multimode cavity QED Ising spin glass

Funding: The authors are grateful for funding support from the Army Research Office (Grant No. W911NF2210261). Y. J. acknowledges support from the Q-NEXT DOE National Quantum Information Science Research Center. J. K., B. M., and H. H. acknowledge support from EPSRC (Grant No. EP/Z533713/1), the Stanford QFARM Initiative, and the Stanford Shoucheng Zhang Graduate Fellowship, respectively.We realize a driven-dissipative Ising spin glass using cavity QED in a novel “4/7” multimode geometry. Gases of ultracold atoms trapped within the cavity by optical tweezers serve as effective spins. They are coupled via randomly signed, all-to-all Ising cavity-mediated interactions. Networks of up to = 25 spins are holographically imaged via cavity emission. The system is driven through a frustrated transverse-field Ising transition, and we show that the entropy of the spin glass states depends on the rate at which the transition is crossed. Despite being intrinsically nonequilibrium, the system exhibits phenomena associated with Parisi’s theory of equilibrium spin glasses, namely, replica symmetry breaking (RSB) and ultrametric structure. For system sizes up to = 16, we measure the Parisi function ⁡(), Edwards-Anderson overlap EA, and ultrametricity correlator; all indicate a deeply ordered spin glass under RSB. The system can serve as an associative memory and enable aging and rejuvenation studies in driven-dissipative spin glasses at the microscopic level.Peer reviewe

Radiological dose assessment of Department of Energy Pinellas Plant waste proposed for disposal at Laidlaw Environmental Services of South Carolina, Inc.

The U.S. Department of Energy (DOE) Pinellas Plant in Largo, FL is proposing to ship and dispose of hazardous sludge, listed as F006 waste, to the Laidlaw Environmental Services of South Carolina, Inc. (Laidlaw) treatment, storage, and disposal facility in Pinewood, South Carolina. This sludge contains radioactive tritium in concentrations of about 28 pCi/g. The objective of this study is to assess the possible radiological impact to workers at the Laidlaw facility and members of the public due to the handling, processing, and burial of the DOE waste containing tritium