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The climate change double whammy: Flood damage and the determinants of flood insurance coverage, the case of post-Katrina New Orleans
This paper advances scholarly debate on the contradictions of environmental risk management measures by analyzing the determinants of flood insurance coverage among a sample of 403 residents in New Orleans, a city undergoing rapid transformation due to post-Katrina rebuilding efforts and anthropogenic modifications of climate, hydrology, and ecology. The paper focuses on several predictors including subjective flood risk perception, trust in government officials, sociodemographic characteristics, and experience with flood damage. Using binary logistic regression, the results show that the likelihood of having flood insurance coverage is associated with past flood damage and socioeconomic status. Older people (over age 65) are more likely to have flood insurance than younger residents. Race, gender, trust, and perceived flood risk are not statistically significant predictors of flood insurance. We connect our findings to the paradoxes and conflictual dynamics of flood insurance, a major risk mitigation measure. As we point out, in flood-prone cities like New Orleans, flood insurance operates as a double whammy: uninsured or underinsured homes face pervasive risk of both flooding and rising insurance premiums under the conditions of global climate change
Towards Rapid Parameter Estimation on Gravitational Waves from Compact Binaries using Interpolated Waveforms
Accurate parameter estimation of gravitational waves from coalescing compact
binary sources is a key requirement for gravitational-wave astronomy.
Evaluating the posterior probability density function of the binary's
parameters (component masses, sky location, distance, etc.) requires computing
millions of waveforms. The computational expense of parameter estimation is
dominated by waveform generation and scales linearly with the waveform
computational cost. Previous work showed that gravitational waveforms from
non-spinning compact binary sources are amenable to a truncated singular value
decomposition, which allows them to be reconstructed via interpolation at fixed
computational cost. However, the accuracy requirement for parameter estimation
is typically higher than for searches, so it is crucial to ascertain that
interpolation does not lead to significant errors. Here we provide a proof of
principle to show that interpolated waveforms can be used to recover posterior
probability density functions with negligible loss in accuracy with respect to
non-interpolated waveforms. This technique has the potential to significantly
increase the efficiency of parameter estimation.Comment: 7 pages, 2 figure
Localizing gravitational wave sources with optical telescopes and combining electromagnetic and gravitational wave data
Neutron star binaries, which are among the most promising sources for the
direct detection of gravitational waves (GW) by ground based detectors, are
also potential electromagnetic (EM) emitters. Gravitational waves will provide
a new window to observe these events and hopefully give us glimpses of new
astrophysics. In this paper, we discuss how EM information of these events can
considerably improve GW parameter estimation both in terms of accuracy and
computational power requirement. And then in return how GW sky localization can
help EM astronomers in follow-up studies of sources which did not yield any
prompt emission. We discuss how both EM source information and GW source
localization can be used in a framework of multi-messenger astronomy. We
illustrate how the large error regions in GW sky localizations can be handled
in conducting optical astronomy in the advance detector era. We show some
preliminary results in the context of an array of optical telescopes called
BlackGEM, dedicated for optical follow-up of GW triggers, that is being
constructed in La Silla, Chile and is expected to operate concurrent to the
advanced GW detectors.Comment: 8 pages, 8 figures, Proceeding for Sant Cugat Forum for Astrophysic
Clues on the evolution of the Carina dwarf spheroidal galaxy from the color distribution of its red giant stars
The thin red giant branch (RGB) of the Carina dwarf spheroidal galaxy appears
at first sight quite puzzling and seemingly in contrast with the presence of
several distinct bursts of star formation. In this Letter, we provide a
measurement of the color spread of red giant stars in Carina based on new BVI
wide-field observations, and model the width of the RGB by means of synthetic
color-magnitude diagrams. The measured color spread, Sigma{V-I}=0.021 +/-
0.005, is quite naturally accounted for by the star-formation history of the
galaxy. The thin RGB appears to be essentially related to the limited age range
of its dominant stellar populations, with no need for a metallicity dispersion
at a given age. This result is relatively robust with respect to changes in the
assumed age-metallicity relation, as long as the mean metallicity over the
galaxy lifetime matches the observed value ([Fe/H] = -1.91 +/- 0.12 after
correction for the age effects). This analysis of photometric data also sets
some constraints on the chemical evolution of Carina by indicating that the
chemical abundance of the interstellar medium in Carina remained low throughout
each episode of star formation even though these episodes occurred over many
Gyr.Comment: 4 pages, 3 figures, accepted for publication in the Astrophysical
Journal Letter
Efficiency of dairy rations containing various quantities of grain
The dairy cow is particularly well adapted for consuming and utilizing large quantities of roughages, though she responds well to grain feeding. The relative quantities of roughage and grain that should be fed are usually determined by the physiologic effects and economic efficiencies of such rations when fed to dairy cattle.
One would hardly expect high.producing cows to maintain a high yield when consuming roughage alone, because such a ration is so bulky that it prevents the intake of sufficient nutrients for maximum production. And yet, very good results have been obtained in certain areas by such a system of feeding. Then, too, the nutrients of roughage crops are usually produced at considerably less cost than those of grain crops (17) (3). Furthermore, rough. ages are more plentiful on most farms than grain crops, especially in recent years when there has been a marked increase in the production of hay and pasture crops at some sacrifice of grain production. Under these conditions the advisability of supplementing roughage rations with grain becomes a question of interest to dairy farmers
Purification and Characterization of a Gamma-Like DNA-Polymerase From \u3ci\u3eChenopodium album\u3c/i\u3e L.
A DNA polymerase activity from mitochondria of the dicotyledonous angiosperm Chenopodium album L. was purified almost 9000 fold by successive column chromatography steps on DEAE cellulose, heparin agarose and ssDNA cellulose. The enzyme was characterized as a gamma-class polymerase, based on its resistance to inhibitors of the nuclear DNA polymerase alpha and its preference for poly(rA).(dT)12-18 over activated DNA in vitro. The molecular weight was estimated to be 80,000 - 90,000. A 3\u27 to 5\u27 exonuclease activity was found to be tightly associated with the DNA polymerase activity through all purification steps. This is the first report of an association between a DNA polymerase and an exonuclease activity in plant mitochondria
Techniques for measuring atmospheric aerosols at the High Resolution Fly's Eye experiment
We describe several techniques developed by the High Resolution Fly's Eye
experiment for measuring aerosol vertical optical depth, aerosol horizontal
attenuation length, and aerosol phase function. The techniques are based on
measurements of side-scattered light generated by a steerable ultraviolet laser
and collected by an optical detector designed to measure fluorescence light
from cosmic-ray air showers. We also present a technique to cross-check the
aerosol optical depth measurement using air showers observed in stereo. These
methods can be used by future air fluorescence experiments.Comment: Accepted for publication in Astroparticle Physics Journal 16 pages, 9
figure
The frequency and properties of young tidal dwarf galaxies in nearby gas-rich groups
We present high-resolution Giant Metrewave Radio Telescope (GMRT) HI
observations and deep Canada-France-Hawaii Telescope (CFHT) optical imaging of
two galaxy groups: NGC 4725/47 and NGC 3166/9. These data are part of a
multi-wavelength unbiased survey of the gas-rich dwarf galaxy populations in
three nearby interacting galaxy groups. The NGC 4725/47 group hosts two tidal
knots and one dIrr. Both tidal knots are located within a prominent HI tidal
tail, appear to have sufficient mass (M_gas~10^8 M_sol) to evolve into
long-lived tidal dwarf galaxies (TDGs) and are fairly young in age. The NGC
3166/9 group contains a TDG candidate, AGC 208457, at least three dIrrs and
four HI knots. Deep CFHT imaging confirms that the optical component of AGC
208457 is bluer -- with a 0.28 mag g-r colour -- and a few Gyr younger than its
purported parent galaxies. Combining the results for these groups with those
from the NGC 871/6/7 group reported earlier, we find that the HI properties,
estimated stellar ages and baryonic content of the gas-rich dwarfs clearly
distinguish tidal features from their classical counterparts. We optimistically
identify four potentially long-lived tidal objects associated to three separate
pairs of interacting galaxies, implying that TDGs are not readily produced
during interaction events as suggested by some recent simulations. The tidal
objects examined in this survey also appear to have a wider variety of
properties than TDGs of similar mass formed in current simulations of
interacting galaxies, which could be the result of pre- or post-formation
environmental influences.Comment: 18 pages, 14 figures, accepted for publication in MNRA
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