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Insight into Stagnating Life Expectancy: Analysing Cause of Death Patterns across Socio-economic Groups
This article analyzes the complexity of female longevity improvements. As socio-economic status is found to influence health and mortality, we partition all individuals, at each age in every year, into five socio-economic groups based on an affluence measure that combine an individual’s income and wealth. We identify the particular socio-economic groups that have been driving the standstill for Danish females. Within each socio-economic group, we further analyze the cause of death patterns. The decline in life expectancy for Danish females is present for four out of five subgroups, however with particular large decreases for the low-middle and middle affluence groups. Cancers, smoking related causes, and other diseases particularly contribute to the stagnation. Moreover, cardiovascular and cerebrovascular diseases are found to be important for capturing the following catch-up in longevity
A comparison of star formation characteristics in different types of irregular galaxies
Two regions of recent star formation in blue irregular galaxies were observed with the IUE in the short wavelength, low dispersion mode. The spectra indicates that the massive star content is similar in these regions and is best fit by massive stars formed in a burst and now are approximately 2.5 to 3.0 million years old
Massive particle creation in a static 1+1 dimensional spacetime
We show explicitly that there is particle creation in a static spacetime.
This is done by studying the field in a coordinate system based on a physical
principle which has recently been proposed. There the field is quantized by
decomposing it into positive and negative frequency modes on a particular
spacelike surface. This decomposition depends explicitly on the surface where
the decomposition is performed, so that an observer who travels from one
surface to another will observe particle production due to the different vacuum
state.Comment: 17 pages, RevTeX, no figure
Aerodynamic characteristics at Mach numbers of 1.5, 1.8, and 2.0 of a blended wing-body configuration with and without integral canards
An exploratory, experimental, and theoretical investigation was made of a cambered, twisted, and blended wing-body concept with and without integral canard surfaces. Theoretical calculations of the static longitudinal and lateral aerodynamic characteristics of the wing-body configurations were compared with the characteristics obtained from tests of a model in the Langley Unitary Plan wind tunnel. Mach numbers of 1.5, 1.8, and 2.0 and a Reynolds number per meter of 6.56 million were used in the calculations and tests. Overall results suggest that planform selection is extremely important and that the supplemental application of new calculation techniques should provide a process for the design of supersonic wings in which spanwise distribution of upwash and leading-edge thrust might be rationally controlled and exploited
IUE observations of luminous blue star associations in irregular galaxies
Two regions of recent star formation in blue irregular galaxies were observed with the IUE in the short wavelength, low dispersion mode. The spectra indicate that the massive star content is similar in these regions and is best fit by massive stars formed in a burst and now approximately 2.5 to 3.0 million years old
International Ultraviolet Explorer observations of amorphous hot galaxies
In order to better understand the nature of star formation processes in amorphous galaxies, short wavelength International Ultraviolet Explorer (IUE) spectra of galaxies NGC 1705 and NGC 1800 were obtained. The IUE data for NGC 1705 were of excellent quality while the low signal-to-noise NGC 1800 observation was useful only as a rough guide to the ultraviolet energy distribution. It was found that NGC 1705 contains a normal mix of OB stars, which is consistent with the nearly constant recent star formation rate inferred from new optical data. The NGC 1800 is likely to have similar properties, and blue galaxies with amorphous structures thus do not show evidence for anomalies in stellar mass distributions. The UV spectra of amorphous galaxies and a variety of other hot extragalactic stellar systems have similar characteristics, which suggests OB stellar populations often are homogeneous in their properties
Coronal hole boundaries at small scales: IV. SOT view Magnetic field properties of small-scale transient brightenings in coronal holes
We study the magnetic properties of small-scale transients in coronal hole.
We found all brightening events are associated with bipolar regions and caused
by magnetic flux emergence followed by cancellation with the pre-existing and
newly emerging magnetic flux. In the coronal hole, 19 of 22 events have a
single stable polarity which does not change its position in time. In eleven
cases this is the dominant polarity. The dominant flux of the coronal hole form
the largest concentration of magnetic flux in terms of size while the opposite
polarity is distributed in small concentrations. In the coronal hole the number
of magnetic elements of the dominant polarity is four times higher than the
non-dominant one. The supergranulation configuration appears to preserve its
general shape during approximately nine hours of observations although the
large concentrations in the network did evolve and were slightly displaced, and
their strength either increased or decreased. The emission fluctuations seen in
the X-ray bright points are associated with reoccurring magnetic cancellation
in the footpoints. Unique observations of an X-ray jet reveal similar magnetic
behaviour in the footpoints, i.e. cancellation of the opposite polarity
magnetic flux. We found that the magnetic flux cancellation rate during the jet
is much higher than in bright points. Not all magnetic cancellations result in
an X-ray enhancement, suggesting that there is a threshold of the amount of
magnetic flux involved in a cancellation above which brightening would occur at
X-ray temperatures. Our study demonstrates that the magnetic flux in coronal
holes is continuously recycled through magnetic reconnection which is
responsible for the formation of numerous small-scale transient events. The
open magnetic flux forming the coronal-hole phenomenon is largely involved in
these transient features.Comment: 19 pages, 18 figures, A&A in pres
Gamma-Ray Bursts are Produced Predominately in the Early Universe
It is known that some observed gamma-ray bursts (GRBs) are produced at
cosmological distances and that the GRB production rate may follow the star
formation rate. We model the BATSE-detected intensity distribution of long GRBs
in order to determine their space density distribution and opening angle
distribution. Our main results are: the lower and upper distance limits to the
GRB production are z 0.24 and >10, respectively; the GRB opening angle follows
an exponential distribution and the mean opening angle is about 0.03 radians;
and the peak luminosity appears to be a better standard candle than the total
energy of a GRB.Comment: 12 pages, 2 figur
A Girsanov approach to slow parameterizing manifolds in the presence of noise
We consider a three-dimensional slow-fast system with quadratic nonlinearity
and additive noise. The associated deterministic system of this stochastic
differential equation (SDE) exhibits a periodic orbit and a slow manifold. The
deterministic slow manifold can be viewed as an approximate parameterization of
the fast variable of the SDE in terms of the slow variables. In other words the
fast variable of the slow-fast system is approximately "slaved" to the slow
variables via the slow manifold. We exploit this fact to obtain a two
dimensional reduced model for the original stochastic system, which results in
the Hopf-normal form with additive noise. Both, the original as well as the
reduced system admit ergodic invariant measures describing their respective
long-time behaviour. We will show that for a suitable metric on a subset of the
space of all probability measures on phase space, the discrepancy between the
marginals along the radial component of both invariant measures can be upper
bounded by a constant and a quantity describing the quality of the
parameterization. An important technical tool we use to arrive at this result
is Girsanov's theorem, which allows us to modify the SDEs in question in a way
that preserves transition probabilities. This approach is then also applied to
reduced systems obtained through stochastic parameterizing manifolds, which can
be viewed as generalized notions of deterministic slow manifolds.Comment: 54 pages, 6 figure
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