28,906 research outputs found
The association between county political inclination and obesity: Results from the 2012 presidential election in the United States.
ObjectiveWe examined whether stable, county-level, voter preferences were significantly associated with county-level obesity prevalence using data from the 2012 US Presidential election. County voting preference for the 2012 Republican Party presidential candidate was used as a proxy for voter endorsement of personal responsibility approaches to reducing population obesity risk versus approaches featuring government-sponsored, multi-sectoral efforts like those recommended by the Centers for Disease Control Centers for Disease Control (CDC, 2009).MethodCartographic visualization and spatial analysis were used to evaluate the geographic clustering of obesity prevalence rates by county, and county-level support for the Republican Party candidate in the 2012 U.S. presidential election. The spatial analysis informed the spatial econometric approach employed to model the relationship between political preferences and other covariates with obesity prevalence.ResultsAfter controlling for poverty rate, percent African American and Latino populations, educational attainment, and spatial autocorrelation in the error term, we found that higher county-level obesity prevalence rates were associated with higher levels of support for the 2012 Republican Party presidential candidate.ConclusionFuture public health efforts to understand and reduce obesity risk may benefit from increased surveillance of this and similar linkages between political preferences and health risks
Dynamical evolution of the mass function and radial profile of the Galactic globular cluster system
Evolution of the mass function (MF) and radial distribution (RD) of the
Galactic globular cluster (GC) system is calculated using an advanced and a
realistic Fokker-Planck (FP) model that considers dynamical friction,
disc/bulge shocks and eccentric cluster orbits. We perform hundreds of FP
calculations with different initial cluster conditions, and then search a
wide-parameter space for the best-fitting initial GC MF and RD that evolves
into the observed present-day Galactic GC MF and RD. By allowing both MF and RD
of the initial GC system to vary, which is attempted for the first time in the
present Letter, we find that our best-fitting models have a higher peak mass
for a lognormal initial MF and a higher cut-off mass for a power-law initial MF
than previous estimates, but our initial total masses in GCs, M_{T,i} =
1.5-1.8x10^8 Msun, are comparable to previous results. Significant findings
include that our best-fitting lognormal MF shifts downward by 0.35 dex during
the period of 13 Gyr, and that our power-law initial MF models well-fit the
observed MF and RD only when the initial MF is truncated at >~10^5 Msun. We
also find that our results are insensitive to the initial distribution of orbit
eccentricity and inclination, but are rather sensitive to the initial
concentration of the clusters and to how the initial tidal radius is defined.
If the clusters are assumed to be formed at the apocentre while filling the
tidal radius there, M_{T,i} can be as high as 6.9x10^8 Msun, which amounts to
~75 per cent of the current mass in the stellar halo.Comment: To appear in May 2008 issue of MNRAS, 386, L6
Nonequilibrium Phase Transitions and a Nonequilibrium Critical Point from Anti-de Sitter Space and Conformal Field Theory Correspondence
We find novel phase transitions and critical phenomena that occur only
outside the linear-response regime of current-driven nonequilibrium states. We
consider the strongly-interacting (3+1)-dimensional N=4 large-Nc SU(Nc)
supersymmetric Yang-Mills theory with a single flavor of fundamental N=2
hypermultiplet as a microscopic theory. We compute its nonlinear non-ballistic
quark-charge conductivity by using the AdS/CFT correspondence. We find that the
system exhibits a novel nonequilibrium first-order phase transition where the
conductivity jumps and the sign of the differential conductivity flips at
finite current density. A nonequilibrium critical point is discovered at the
end point of the first-order regime. We propose a nonequilibrium steady-state
analogue of thermodynamic potential in terms of the gravity-dual theory in
order to define the transition point. Nonequilibrium analogues of critical
exponents are proposed as well. The critical behavior of the conductivity is
numerically confirmed on the basis of these proposals. The present work
provides a new example of nonequilibrium phase transitions and nonequilibrium
critical points.Comment: 5 pages, 2 figures; v2: slightly short version is published in PRL.
The title is changed in the PRL forma
Optimal trajectories for efficient atomic transport without final excitation
We design optimal harmonic-trap trajectories to transport cold atoms without
final excitation, combining an inverse engineering techniqe based on
Lewis-Riesenfeld invariants with optimal control theory. Since actual traps are
not really harmonic, we keep the relative displacement between the center of
mass and the trap center bounded. Under this constraint, optimal protocols are
found according to different physical criteria. The minimum time solution has a
"bang-bang" form, and the minimum displacement solution is of "bang-off-bang"
form. The optimal trajectories for minimizing the transient energy are also
discussed.Comment: 10 pages, 7 figure
Monolithic arrays of surface emitting laser NOR logic devices
Monolithic, cascadable, laser-logic-device arrays have been realized and characterized. The monolithic surface-emitting laser logic (SELL) device consists of an AlGaAs superlattice lasing around 780 nm connected to a heterojunction phototransistor (HPT) in parallel and a resistor in series. Arrays up to 8×8 have been fabricated, and 2×2 arrays show uniform characteristics. The optical logic output is switched off with 40 μW incident optical input
Monolithic arrays of surface emitting laser NOR logic devices
Monolithic, cascadable, laser-logic-device arrays have been realized and characterized. The monolithic surface-emitting laser logic (SELL) device consists of an AlGaAs superlattice lasing around 780 nm connected to a heterojunction phototransistor (HPT) in parallel and a resistor in series. Arrays up to 8×8 have been fabricated, and 2×2 arrays show uniform characteristics. The optical logic output is switched off with 40 μW incident optical input
Holographic Meson Spectra in the Dense Medium with Chiral Condensate
We study two effects on the meson spectra by using the AdS/CFT
correspondence where the corrections from the chiral condensate and the
quark density are controlled by the gravitational backreaction of the massive
scalar field and U(1) gauge field respectively. The dual geometries with zero
and nonzero current quark masses are obtained numerically. We discuss meson
spectra and binding energy of heavy quarkonium with the subleading corrections
in the hard wall model.Comment: 16 pages, 4 figure
Walls in supersymmetric massive nonlinear sigma model on complex quadric surface
The Bogomol'nyi-Prasad-Sommerfield (BPS) multiwall solutions are constructed
in a massive Kahler nonlinear sigma model on the complex quadric surface,
Q^N=SO(N+2)/[SO(N)\times SO(2)] in 3-dimensional space-time. The theory has a
non-trivial scalar potential generated by the Scherk-Schwarz dimensional
reduction from the massless nonlinear sigma model on Q^N in 4-dimensional
space-time and it gives rise to 2[N/2+1] discrete vacua. The BPS wall solutions
connecting these vacua are obtained based on the moduli matrix approach. It is
also shown that the moduli space of the BPS wall solutions is the complex
quadric surface Q^N.Comment: 42 pages, 30 figures, typos corrected, version to appear in PR
The order-disorder transition in colloidal suspensions under shear flow
We study the order-disorder transition in colloidal suspensions under shear
flow by performing Brownian dynamics simulations. We characterize the
transition in terms of a statistical property of time-dependent maximum value
of the structure factor. We find that its power spectrum exhibits the power-law
behaviour only in the ordered phase. The power-law exponent is approximately -2
at frequencies greater than the magnitude of the shear rate, while the power
spectrum exhibits the -type fluctuations in the lower frequency regime.Comment: 11 pages, 10 figures, v.2: We have made some small improvements on
presentation
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