5,781 research outputs found
Maryland Chartbook of Minority Health And Minority Health Disparities Data With Sections on Gender-specific Health And Jurisdiction-specific Health
The Office of Minority Health and Health Disparities (MHHD) was established in the Maryland Department of Health and Mental Hygiene in 2004 by legislation passed in the Maryland General Assembly session of that same year. One of the charges to MHHD is the compilation and distribution of minority health and health disparities data. This Chartbook is one response to that charge. Adequate and accurate data are essential to any effort to identify and address health problems in general, and health disparities in particular. With regard to health disparities, whether defined by ethnicity/race or other factors (geography, gender, income, education, etc.), data are required to complete three essential tasks: 1. Identify and measure disparities 2. Determine the causes of the disparity and plan interventions 3. Track progress toward eliminating health disparities The compilation of Maryland health disparities data in this Chartbook is intended to enable each of these three critical functions.https://health.maryland.gov/hd/mdchartbook.ht
Analysis of the phenomenon of speculative trading in one of its basic manifestations: postage stamp bubbles
We document and analyze the empirical facts concerning one of the clearest
evidence of speculation in financial trading as observed in the postage
collection stamp market. We unravel some of the mechanisms of speculative
behavior which emphasize the role of fancy and collective behavior. In our
conclusion, we propose a classification of speculative markets based on two
parameters, namely the amplitude of the price peak and a second parameter that
measures its ``sharpness''. This study is offered to anchor modeling efforts to
realistic market constraints and observations.Comment: 9 pages, 5 figures and 2 tables, in press in Int. J. Mod. Phys.
An exact solution for 2+1 dimensional critical collapse
We find an exact solution in closed form for the critical collapse of a
scalar field with cosmological constant in 2+1 dimensions. This solution agrees
with the numerical simulation done by Pretorius and Choptuik of this system.Comment: 5 pages, 5 figures, Revtex. New comparison of analytic and numerical
solutions beyond the past light cone of the singularity added. Two new
references added. Error in equation (21) correcte
Joint stiffness is heritable and associated with fibrotic conditions and joint replacement
ObjectiveJoint stiffness is a common, debilitating, age-related symptom, which may be seen after total joint replacement (TJR). Stiffness also occurs in fibrotic conditions such as shoulder capsulitis and Dupuytren's contracture. We speculated that the two traits (TJR and fibrotic disease) are linked pathogenically.MethodsUsing the TwinsUK NIHR BRC BioResource we tested the hypotheses that 1) joint (hip and knee) stiffness, TJR (hip and knee), and fibrotic conditions are associated and 2) genetic factors contribute to them.ResultsParticipating twins (n = 9718) had completed self-reported questionnaires on the traits of interest. All three traits were significantly associated with increasing age and body mass index (BMI), as well as female sex, on univariate analysis. Multivariable logistic regression analyses showed a significant association between TJR and joint stiffness (OR = 3.96, 95% confidence interval, CI 2.77-5.68) and between fibrotic conditions and joint stiffness (OR = 2.39, 1.74-3.29), adjusting for age, sex, BMI and twin relatedness. Monozygotic versus dizygotic intraclass correlations gave heritability estimates for TJR = 46% and joint stiffness = 32%.ConclusionThat fibrotic conditions, joint stiffness and TJR are significantly associated suggests a common disease process, possibly fibrosis, which is genetically mediated
Masses and Mixings in a Grand Unified Toy Model
The generation of the fermion mass hierarchy in the standard model of
particle physics is a long-standing puzzle. The recent discoveries from
neutrino physics suggests that the mixing in the lepton sector is large
compared to the quark mixings. To understand this asymmetry between the quark
and lepton mixings is an important aim for particle physics. In this regard,
two promising approaches from the theoretical side are grand unified theories
and family symmetries. In this note we try to understand certain general
features of grand unified theories with Abelian family symmetries by taking the
simplest SU(5) grand unified theory as a prototype. We construct an SU(5) toy
model with family symmetry
that, in a natural way, duplicates the observed mass hierarchy and mixing
matrices to lowest approximation. The system for generating the mass hierarchy
is through a Froggatt-Nielsen type mechanism. One idea that we use in the model
is that the quark and charged lepton sectors are hierarchical with small mixing
angles while the light neutrino sector is democratic with larger mixing angles.
We also discuss some of the difficulties in incorporating finer details into
the model without making further assumptions or adding a large scalar sector.Comment: 21 pages, 2 figures, RevTeX, v2: references updated and typos
corrected, v3: updated top quark mass, comments on MiniBooNE result, and
typos correcte
Mixed Sneutrinos, Dark Matter and the LHC
We study the phenomenology of supersymmetric models in which gauge-singlet
scalars mix with the MSSM sneutrinos through weak-scale terms. After
reviewing the constraints on mixed-sneutrino dark matter from measurements of
and from direct-detection experiments, we explore
mixed-sneutrino signatures relevant to the LHC. For a mixed-sneutrino LSP and a
right-handed slepton NLSP, decays of the lightest neturalino can produce
opposite-sign, same-flavor (OSSF) dileptons with an invariant-mass distribution
shifted away from the kinematic endpoint. In different parameter regions, the
charginos and neutralinos produced in cascades all decay dominantly to the
lighter sneutrinos, leading to a kinematic edge in the jet-lepton
invariant-mass distribution from the decay chain \tilde{q} \to \chi^- q \to
\snu^* l q, without an OSSF dilepton signature. We explore the possibility of
using mass estimation methods to distinguish this mixed-sneutrino jet-lepton
signature from an MSSM one. Finally, we consider signatures associated with
Higgs-lepton or -lepton production in cascades involving the heavier
sneutrinos
Generating entangled fermions by accelerated measurements on the vacuum
It is shown that accelerated projective measurements on the vacuum of a free
Dirac spinor field results in an entangled state for an inertial observer. The
physical mechanism at work is the Davies-Unruh effect. The produced state is
always entangled and its entanglement increases as a function of the
acceleration, reaching maximal entanglement in the asymptotic limit of infinite
acceleration where Bell states are produced.Comment: 4 pages, 2 figures, REVTeX
Objective properties from subjective quantum states: Environment as a witness
We study the emergence of objective properties in open quantum systems. In
our analysis, the environment is promoted from a passive role of reservoir
selectively destroying quantum coherence, to an active role of amplifier
selectively proliferating information about the system. We show that only
preferred pointer states of the system can leave a redundant and therefore
easily detectable imprint on the environment. Observers who--as it is almost
always the case--discover the state of the system indirectly (by probing a
fraction of its environment) will find out only about the corresponding pointer
observable. Many observers can act in this fashion independently and without
perturbing the system: they will agree about the state of the system. In this
operational sense, preferred pointer states exist objectively.Comment: 5 pages, 1 figure, extensive changes, presentation improve
The lattice stiffening transition in UO2 single crystals
The effective Debye temperatures (θDE) of the surface region of UO2 single crystals, prepared by the hydrothermal synthesis technique, were obtained from temperature-dependent x-ray photoemission in the temperature range of 300 K–623 K. A lattice stiffening transition, characterized by different regions of different effective Debye temperature, 500 ± 59 K below 475 K and 165 ± 21 K above 475 K is identified. A comparison of the temperature dependence of the effective UO2 Debye temperature, with the changes in the lattice expansion coefficient for UO2, support strong lattice-phonon interaction arising from the Jahn–Teller distortion
Extended phase space thermodynamics for charged and rotating black holes and Born-Infeld vacuum polarization
We investigate the critical behaviour of charged and rotating AdS black holes
in d spacetime dimensions, including effects from non-linear electrodynamics
via the Born-Infeld action, in an extended phase space in which the
cosmological constant is interpreted as thermodynamic pressure. For
Reissner-Nordstrom black holes we find that the analogy with the Van der Walls
liquid-gas system holds in any dimension greater than three, and that the
critical exponents coincide with those of the Van der Waals system. We find
that neutral slowly rotating black holes in four space-time dimensions also
have the same qualitative behaviour. However charged and rotating black holes
in three spacetime dimensions do not exhibit critical phenomena. For
Born-Infeld black holes we define a new thermodynamic quantity B conjugate to
the Born-Infeld parameter b that we call Born-Infeld vacuum polarization. We
demonstrate that this quantity is required for consistency of both the first
law of thermodynamics and the corresponding Smarr relation.Comment: 23 pages, 32 figures, v2: minor changes, upgraded reference
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