2,787 research outputs found
Updated Trends in Child Maltreatment, 2013.
New national data for 2013 show continued declines in child maltreatment, after a one year discontinuity (2012) in which some rates briefly increased. But from 2012 to 2013, sexual abuse declined 4%, physical abuse declined 3%, child maltreatment fatalities declined 7% and overall substantiated child maltreatment declined 1%. Neglect by contrast rose 1%
Updated trends in Child Maltreatment, 2012.
National statistics from 2012 showed increases in some forms of child maltreatment for the first time in many years. While overall substantiated child maltreatment was flat from 2011 to 2012, there was a 2% rise in sexual abuse and a 5% rise in physical abuse. Neglect declined 3%, but child maltreatment fatalities rose 4% from 1557 to 1620
Relativistic stars in f(R) gravity, and absence thereof
Several f(R) modified gravity models have been proposed which realize the
correct cosmological evolution and satisfy solar system and laboratory tests.
Although nonrelativistic stellar configurations can be constructed, we argue
that relativistic stars cannot be present in such f(R) theories. This problem
appears due to the dynamics of the effective scalar degree of freedom in the
strong gravity regime. Our claim thus raises doubts on the viability of f(R)
models.Comment: 9 pages, 7 figures, v2: references added, minor corrections, version
accepted for publication in PR
Can the standard international business cycle model explain the relation between trade and comovement?
Recent empirical research finds that pairs of countries with stronger trade linkages tend to have more highly correlated business cycles. We assess whether the standard international business cycle framework can replicate this intuitive result. We employ a three-country model with transportation costs. We simulate the effects of increased goods market integration under two asset market structures: complete markets and international financial autarky. Our main finding is that under both asset market structures the model can generate stronger correlations for pairs of countries that trade more, but the increased correlation falls far short of the empirical findings. Even when we control for the fact that most country pairs are small with respect to the rest of the world, the model continues to fall short. We also conduct additional simulations that allow for increased trade with the third country or increased TFP shock comovement to affect the country pair’s business cycle comovement. These simulations are helpful in highlighting channels that could narrow the gap between the empirical findings and the predictions of the model.Business cycles ; International trade
Dissipation-induced pure Gaussian state
This paper provides some necessary and sufficient conditions for a
generalMarkovian Gaussian master equation to have a unique pure steady state.
The conditions are described by simple matrix equations; thus the so-called
environment engineering problem for pure-Gaussian-state preparation can be
straightforwardly dealt with in the linear algebraic framework. In fact, based
on one of those conditions, for an arbitrary given pure Gaussian state,we
obtain a complete parametrization of the Gaussian master equation having that
state as a unique steady state; this leads to a systematic procedure for
engineering a desired dissipative system.We demonstrate some examples including
Gaussian cluster states.Comment: 8 page
Triviality and vacuum stability bounds in the three-loop neutrino mass model
We study theoretical constraints on the parameter space under the conditions
from vacuum stability and triviality in the three-loop radiative seesaw model
with TeV-scale right-handed neutrinos which are odd under the parity. In
this model, some of the neutrino Yukawa coupling constants can be of the order
of one. Requirement of strongly first order phase transition for successful
electroweak baryogenes is also prefers order-one coupling constants in the
scalar sector. Hence, it is important to clarify whether this model satisfies
those theoretical conditions up to a given cutoff scale. It is found that the
model can be consistent up to the scale above 10 TeV in the parameter region
where the neutrino data, the lepton flavor violation data, the thermal relic
abundance of dark matter as well as the requirement from the strongly first
order phase transition are satisfied.Comment: 22 pages, 14 figure
Curvature effect on nuclear pasta: Is it helpful for gyroid appearance?
In supernova cores and neutron star crusts, nuclei are thought to deform to
rodlike and slablike shapes, which are often called nuclear pasta. We study the
equilibrium properties of the nuclear pasta by using a liquid drop model with
curvature corrections. It is confirmed that the curvature effect acts to lower
the transition densities between different shapes. We also examine the gyroid
structure, which was recently suggested as a different type of nuclear pasta by
analogy with the polymer systems. The gyroid structure investigated in this
paper is approximately formulated as an extension of the periodic minimal
surface whose mean curvature vanishes. In contrast to our expectations, we find
from the present approximate formulation that the curvature corrections act to
slightly disfavor the appearance of the gyroid structure. By comparing the
energy corrections in the gyroid phase and the hypothetical phases composed of
d-dimensional spheres, where d is a general dimensionality, we show that the
gyroid is unlikely to belong to a family of the generalized dimensional
spheres.Comment: 14 pages, 8 figure
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