158 research outputs found
Economy-wide impacts of consumer responses to environmental information disclosure in Tokyo and the other parts of Japan
Environmental problems such as global warming due to GHG emissions have necessitated some constraint in our economic activities, as many countries and many people around the world are concerned about these issues. Environmental and economic policies such as carbon tax are one such constraint. A tax policy can be interpreted as a desirable method that can lead the economy, which has to pay the social cost of false economic activity or market failure, to a more optimal path. However, this policy will surely raise prices of goods. On the one hand, this price rise will benefit the public sector, but on the other hand, consumers demand will decline. The magnitude of the reduction usually depends on the price elasticity of demand, and the increase in government gain depends on the necessity of the goods for the people. Therefore, it is not necessarily trivial to ask whether the total effect of rising energy prices will be negative. In addition, nowadays, many people are concerned about environmental problems, and there are indications that consumers tend to change their purchasing behavior regarding certain goods to take environmental concerns into account even if this necessitates paying a higher price. This paper will empirically prove how the rise in oil and gas prices due to environmental policies like carbon tax affects the total production/consumption when we take into account the change in consumer behavior reflecting their attitudes toward preventing global warming. The main result of the analysis using an input-output model and price elasticity of demand in several sectors will show that most of sectors do not experience a decline in production after a price rise except the biggest sector, real estate. In Japan, real estate might be the main target to support for consumerfs purchasing from the viewpoint of economic policy.consumer behavior; disclosure of information about environmental damage; energy price rising effect; price elasticity of demand; International Input-Output model.
The bar-mode instability in differentially rotating neutron stars: Simulations in full general relativity
We study the dynamical stability against bar-mode deformation of rapidly
spinning neutron stars with differential rotation. We perform fully
relativistic 3D simulations of compact stars with , where is
the total gravitational mass and the equatorial circumferential radius. We
adopt an adiabatic equation of state with adiabatic index . As in
Newtonian theory, we find that stars above a critical value of (where is the rotational kinetic energy and the gravitational
binding energy) are dynamically unstable to bar formation. For our adopted
choices of stellar compaction and rotation profile, the critical value of
is , only slightly smaller than the
well-known Newtonian value for incompressible Maclaurin spheroids.
The critical value depends only very weakly on the degree of differential
rotation for the moderate range we surveyed. All unstable stars form bars on a
dynamical timescale. Models with sufficiently large subsequently form
spiral arms and eject mass, driving the remnant to a dynamically stable state.
Models with moderately large do not develop spiral
arms or eject mass but adjust to form dynamically stable ellipsoidal-like
configurations. If the bar-mode instability is triggered in supernovae collapse
or binary neutron star mergers, it could be a strong and observable source of
gravitational waves. We determine characteristic wave amplitudes and
frequencies.Comment: 17 pages, accepted for publication in AP
Non-conformally flat initial data for binary compact objects
A new method is described for constructing initial data for a binary
neutron-star (BNS) system in quasi-equilibrium circular orbit. Two formulations
for non-conformally flat data, waveless (WL) and near-zone helically symmetric
(NHS), are introduced; in each formulation, the Einstein-Euler system, written
in 3+1 form on an asymptotically flat spacelike hypersurface, is exactly solved
for all metric components, including the spatially non-conformally flat
potentials, and for irrotational flow. A numerical method applicable to both
formulations is explained with an emphasis on the imposition of a spatial gauge
condition. Results are shown for solution sequences of irrotational BNS with
matter approximated by parametrized equations of state that use a few segments
of polytropic equations of state. The binding energy and total angular momentum
of solution sequences computed within the conformally flat --
Isenberg-Wilson-Mathews (IWM) -- formulation are closer to those of the third
post-Newtonian (3PN) two point particles up to the closest orbits, for the more
compact stars, whereas sequences resulting from the WL/NHS formulations deviate
from the 3PN curve even more for the sequences with larger compactness. We
think it likely that this correction reflects an overestimation in the IWM
formulation as well as in the 3PN formula, by cycle in the
gravitational wave phase during the last several orbits. The work suggests that
imposing spatial conformal flatness results in an underestimate of the
quadrupole deformation of the components of binary neutron-star systems in the
last few orbits prior to merger.Comment: 22 pages, 7 figure
On the Maximum Mass of Differentially Rotating Neutron Stars
We construct relativistic equilibrium models of differentially rotating
neutron stars and show that they can support significantly more mass than their
nonrotating or uniformly rotating counterparts. We dynamically evolve such
``hypermassive'' models in full general relativity and show that there do exist
configurations which are dynamically stable against radial collapse and bar
formation. Our results suggest that the remnant of binary neutron star
coalescence may be temporarily stabilized by differential rotation, leading to
delayed collapse and a delayed gravitational wave burst.Comment: 4 pages, 2 figures, uses emulateapj.sty; to appear in ApJ Letter
Innermost stable circular orbits around relativistic rotating stars
We investigate the innermost stable circular orbit (ISCO) of a test particle
moving on the equatorial plane around rotating relativistic stars such as
neutron stars. First, we derive approximate analytic formulas for the angular
velocity and circumferential radius at the ISCO making use of an approximate
relativistic solution which is characterized by arbitrary mass, spin, mass
quadrupole, current octapole and mass -pole moments. Then, we show that
the analytic formulas are accurate enough by comparing them with numerical
results, which are obtained by analyzing the vacuum exterior around numerically
computed geometries for rotating stars of polytropic equation of state. We
demonstrate that contribution of mass quadrupole moment for determining the
angular velocity and, in particular, the circumferential radius at the ISCO
around a rapidly rotating star is as important as that of spin.Comment: 12 pages, 2 figures, accepted for publication in Phys. Rev.
Magnetorotational collapse of massive stellar cores to neutron stars: Simulations in full general relativity
We study magnetohydrodynamic (MHD) effects arising in the collapse of
magnetized, rotating, massive stellar cores to proto-neutron stars (PNSs). We
perform axisymmetric numerical simulations in full general relativity with a
hybrid equation of state. The formation and early evolution of a PNS are
followed with a grid of 2500 x 2500 zones, which provides better resolution
than in previous (Newtonian) studies. We confirm that significant differential
rotation results even when the rotation of the progenitor is initially uniform.
Consequently, the magnetic field is amplified both by magnetic winding and the
magnetorotational instability (MRI). Even if the magnetic energy E_EM is much
smaller than the rotational kinetic energy T_rot at the time of PNS formation,
the ratio E_EM/T_rot increases to 0.1-0.2 by the magnetic winding. Following
PNS formation, MHD outflows lead to losses of rest mass, energy, and angular
momentum from the system. The earliest outflow is produced primarily by the
increasing magnetic stress caused by magnetic winding. The MRI amplifies the
poloidal field and increases the magnetic stress, causing further angular
momentum transport and helping to drive the outflow. After the magnetic field
saturates, a nearly stationary, collimated magnetic field forms near the
rotation axis and a Blandford-Payne type outflow develops along the field
lines. These outflows remove angular momentum from the PNS at a rate given by
\dot{J} \sim \eta E_EM C_B, where \eta is a constant of order 0.1 and C_B is a
typical ratio of poloidal to toroidal field strength. As a result, the rotation
period quickly increases for a strongly magnetized PNS until the degree of
differential rotation decreases. Our simulations suggest that rapidly rotating,
magnetized PNSs may not give rise to rapidly rotating neutron stars.Comment: 28 pages, 20 figures, accepted for publication in Phys. Rev.
Identification and characterization of neural crest-derived cells in adult periodontal ligament of mice
Cells derived from the neural crest (NC) contribute to the development of several adult tissues, including tooth and periodontal tissue. Here, two transgenic lines, Wnt1-Cre/ZEG and P0-Cre/ZEGwere analyzed to determine the fate and distribution of neural crest cells (NCCs) in adult mouse periodontal ligament (PDL)
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