9,387 research outputs found
How Will the Patient Protection and Affordable Care Act of 2010 Affect Children?
Summarizes how reform provisions including the mandate, expanded Medicaid coverage, and changes to parents' coverage will affect children in families of different income levels. Explores possible limitations for Children's Health Insurance Programs
Improving the Lives of Young Children: The Role of Developmental Screenings in Medicaid and CHIP
Outlines barriers to early identification of health, developmental, or behavioral problems. Recommends policies to increase Medicaid and Children's Health Insurance Program enrollment, Well-Child Visits and screenings, and use of data to improve policies
Improving the Lives of Young Children: Increasing Referrals and Follow-Up Treatment in Medicaid and CHIP
Outlines factors limiting referrals and treatment for children in public insurance programs, including low reimbursement rates and complex billing rules and fragmentation between primary care and treatment providers. Recommends state policy options
Setting Income Thresholds in Medicaid/SCHIP: Which Children Should Be Eligible?
Outlines the debate over raising income limits for eligibility in Medicaid and State Children's Health Insurance Programs. Examines how employer-sponsored insurance costs have outpaced income growth and considers the implications for the uninsured rate
Current-driven filamentation upstream of magnetized relativistic collisionless shocks
The physics of instabilities in the precursor of relativistic collisionless
shocks is of broad importance in high energy astrophysics, because these
instabilities build up the shock, control the particle acceleration process and
generate the magnetic fields in which the accelerated particles radiate. Two
crucial parameters control the micro-physics of these shocks: the magnetization
of the ambient medium and the Lorentz factor of the shock front; as of today,
much of this parameter space remains to be explored. In the present paper, we
report on a new instability upstream of electron-positron relativistic shocks
and we argue that this instability shapes the micro-physics at moderate
magnetization levels and/or large Lorentz factors. This instability is seeded
by the electric current carried by the accelerated particles in the shock
precursor as they gyrate around the background magnetic field. The compensation
current induced in the background plasma leads to an unstable configuration,
with the appearance of charge neutral filaments carrying a current of the same
polarity, oriented along the perpendicular current. This ``current-driven
filamentation'' instability grows faster than any other instability studied so
far upstream of relativistic shocks, with a growth rate comparable to the
plasma frequency. Furthermore, the compensation of the current is associated
with a slow-down of the ambient plasma as it penetrates the shock precursor (as
viewed in the shock rest frame). This slow-down of the plasma implies that the
``current driven filamentation'' instability can grow for any value of the
shock Lorentz factor, provided the magnetization \sigma <~ 10^{-2}. We argue
that this instability explains the results of recent particle-in-cell
simulations in the mildly magnetized regime.Comment: 14 pages, 8 figures; to appear in MNRA
Applications of TIMS data in agricultural areas and related atmospheric considerations
While much of traditional remote sensing in agricultural research was limited to the visible and reflective infrared, advances in thermal infrared remote sensing technology are adding a dimension to digital image analysis of agricultural areas. The Thermal Infrared Multispectral Scanner (TIMS) an airborne sensor having six bands over the nominal 8.2 to 12.2 m range, offers the ability to calculate land surface emissivities unlike most previous singular broadband sensors. Preliminary findings on the utility of the TIMS for several agricultural applications and related atmospheric considerations are discussed
The Health Status of New Medicaid Enrollees Under Health Reform
Examines the demographic and health data of those newly eligible for Medicaid coverage, whether younger and healthier or older and less healthy than current enrollees, and how they will affect costs depending on participation rates
Prospects for Reducing Uninsured Rates Among Children: How Much Can Premium Assistance Programs Help?
Examines the efficacy of premium assistance under Medicaid and State Children's Health Insurance Programs in extending coverage for children through a parent's employer-sponsored insurance. Considers policy implications for expanding public insurance
Particle Transport in intense small scale magnetic turbulence with a mean field
Various astrophysical studies have motivated the investigation of the
transport of high energy particles in magnetic turbulence, either in the source
or en route to the observation sites. For strong turbulence and large rigidity,
the pitch-angle scattering rate is governed by a simple law involving a mean
free path that increases proportionally to the square of the particle energy.
In this paper, we show that perpendicular diffusion deviates from this behavior
in the presence of a mean field. We propose an exact theoretical derivation of
the diffusion coefficients and show that a mean field significantly changes the
transverse diffusion even in the presence of a stronger turbulent field. In
particular, the transverse diffusion coefficient is shown to reach a finite
value at large rigidity instead of increasing proportionally to the square of
the particle energy. Our theoretical derivation is corroborated by a dedicated
Monte Carlo simulation. We briefly discuss several possible applications in
astrophysics.Comment: (9 pages, 6 figures, revised version with minor changes
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