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Gains in Life Expectancy Associated with Higher Education in Men
Background: Many studies show large differences in life expectancy across the range of education, intelligence, and socio-economic status. As educational attainment, intelligence, and socio-economic status are highly interrelated, appropriate methods are required to disentangle their separate effects. The aim of this paper is to present a novel method to estimate gains in life expectancy specifically associated with increased education. Our analysis is based on a structural model in which education level, IQ at age 18 and mortality all depend on (latent) intelligence. The model allows for (selective) educational choices based on observed factors and on an unobserved factor capturing intelligence. Our estimates are based on information from health examinations of military conscripts born in 1944–1947 in The Netherlands and their vital status through age 66 (n = 39,798). Results: Our empirical results show that men with higher education have lower mortality. Using structural models to account for education choice, the estimated gain in life expectancy for men moving up one educational level ranges from 0.3 to 2 years. The estimated gain in months alive over the observational period ranges from -1.2 to 5.7 months. The selection effect is positive and amounts to a gain of one to two months. Decomposition of the selection effect shows that the gain from selection on (latent) intelligence is larger than the gain from selection on observed factors and amounts to 1.0 to 1.7 additional months alive. Conclusion: Our findings confirm the strong selection into education based on socio-economic status and intelligence. They also show significant higher life expectancy among individuals with higher education after the selectivity of education choice has been taken into account. Based on these estimates, it is plausible therefore that increases in education could lead to increases in life expectancy
War- and famine-related excess mortality among civilians in the Netherlands, 1944-1945
National estimates exist for war- and famine-related deaths in the Netherlands during the last stages of World War II, but no such estimates are available at the local level. To fill this information gap, this article aims at mapping and visualizing the timing of war- and famine-related excess mortality by municipality among the civilian population within the Netherlands. We use mortality statistics at the level of municipalities because these are the smallest administrative units for which this information is available. We use a seasonally adjusted mortality model combined with a difference-in-difference approach to estimate the number of excess deaths in the period between January 1944 and July 1945 separately for each Dutch municipality
A high sensitivity HI survey of the sky at delta < -25 deg Final data release
We present the final data release of the high sensitivity lambda 21-cm
neutral hydrogen survey of the sky south of delta < -25 degr. A total of 50980
positions lying on a galactic coordinate grid with points spaced by (Delta l,
Delta b) = ((0.5 deg)/cos b, 0.5 deg) were observed with the 30-m dish of the
Instituto Argentino de Radioastronomia (IAR). The angular resolution of the
survey is HPBW = 0.5 deg and the velocity coverage spans the interval -450 km/s
to +400 km/s (LSR). The velocity resolution is 1.27 km/s and the final rms
noise of the entire database is 0.07 K. The data are corrected for stray
radiation and converted to brightness temperatures.Comment: 10 pages, 10 figures, accepted for publication by Astronomy &
Astrophysic
The Effect of Star Formation History on the Inferred Initial Stellar Mass Function
Peaks and lulls in the star formation rate (SFR) over the history of the
Galaxy produce plateaux and declines in the present day mass function (PDMF)
where the main-sequence lifetime overlaps the age and duration of the SFR
variation. These PDMF features can be misinterpreted as the form of the
intrinsic stellar initial mass function (IMF) if the star formation rate is
assumed to be constant or slowly varying with time. This effect applies to all
regions that have formed stars for longer than the age of the most massive
stars, including OB associations, star complexes, and especially galactic field
stars. Related problems may apply to embedded clusters. Evidence is summarized
for temporal SFR variations from parsec scales to entire galaxies, all of which
should contribute to inferred IMF distortions. We give examples of various star
formation histories to demonstrate the types of false IMF structures that might
be seen. These include short-duration bursts, stochastic histories with
log-normal amplitude distributions, and oscillating histories with various
periods and phases. The inferred IMF should appear steeper than the intrinsic
IMF over mass ranges where the stellar lifetimes correspond to times of
decreasing SFRs; shallow portions of the inferred IMF correspond to times of
increasing SFRs. If field regions are populated by dispersed clusters and
defined by their low current SFRs, then they should have steeper inferred IMFs
than the clusters. The SFRs required to give the steep field IMFs in the LMC
and SMC are determined. Structure observed in several determinations of the
Milky Way field star IMF can be accounted for by a stochastic and bursty star
formation history.Comment: accepted by ApJ for 1 Jan 2006, Vol 636, 12 pages + 6 figure
OB Stars in the Solar Neighborhood I: Analysis of their Spatial Distribution
We present a newly-developed, three-dimensional spatial classification
method, designed to analyze the spatial distribution of early type stars within
the 1 kpc sphere around the Sun. We propose a distribution model formed by two
intersecting disks -the Gould Belt (GB) and the Local Galactic Disk (LGD)-
defined by their fundamental geometric parameters. Then, using a sample of
about 550 stars of spectral types earlier than B6 and luminosity classes
between III and V, with precise photometric distances of less than 1 kpc, we
estimate for some spectral groups the parameters of our model, as well as
single membership probabilities of GB and LGD stars, thus drawing a picture of
the spatial distribution of young stars in the vicinity of the Sun.Comment: 28 pages including 9 Postscript figures, one of them in color.
Accepted for publication in The Astronomical Journal, 30 January 200
Autoantibodies against MDA-LDL in subjects with severe and minor atherosclerosis and healthy population controls
Autoantibodies against oxidized low-density lipoprotein (LDL) have been reported to be associated with atherosclerosis. However, data are not consistent. We compared the titres of autoantibodies to malondialdehyde-modified LDL in three groups, a case group with angiographically documented severe coronary stenosis (> 80% stenosis in at least 1 vessel, n = 47), a hospital control group with minor stenosis on the coronary angiography (< 50% stenosis in all three major vessels, n = 47) and a healthy population control group with no history of coronary heart disease (n = 49). Age ranged from 26 to 68 years. Subjects were frequency-matched for gender distribution and storage time of the blood samples. No relevant differences in autoantibody titre between case and control groups were found. The mean autoantibody titres (± S.D.) were 1.44 ± 1.82, 1.46 ± 1.40 and 1.62 ± 1.95 for cases, hospital controls and population controls, respectively. No correlations were found between autoantibody titre and age, number of cigarettes smoked and LDL or total cholesterol. Autoantibody titres were correlated wit
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