567 research outputs found
Funding Resilient Infrastructure in New Jersey: Attitudes Following a Natural Disaster
Recent major natural disasters in New Jersey have demonstrated the need to increase the resilience of transportation infrastructure. This research examines public attitudes toward revenue sources that can be dedicated to protecting vulnerable areas, most notably the transportation linkages on which the state depends. A statewide survey was conducted to gather data approximately four months following Superstorm Sandy, the costliest natural disaster in the state’s history. The authors’ objective was to sample public attitudes while the impacts of the disaster were still fresh. They found little support for temporary tax increases to improve resiliency, with the most positive support for taxing visitors (i.e., a hotel and recreational tax) and for a 30-year bond measure (i.e., taxing the future). This observation seemingly contradicts broad support for investing in new infrastructure, as well as maintaining and protecting existing infrastructure. Multivariate analysis to understand the underlying attitudes toward raising revenue found that more left-leaning or communitarian attitudes are associated with more support for gasoline, income, or sales taxes devoted to mitigating vulnerability. Those who supported investment in transit and protecting infrastructure also were more likely to support these taxes. There was no parallel finding of factors associated with taxing visitors or issuing bonds
Claus-Wilhelm Canaris: Die Vertrauenshaftung im deutschen Privatrecht – Eine Würdigung zum »50. Jubiläum«
Die Vertrauenshaftung im deutschen Privatrecht ist auch 50 Jahre nach ihrem Erscheinen in der Privatrechtswissenschaft von Bedeutung. Der Beitrag gibt zunächst Aufschluss über den Werdegang von Claus-Wilhelm Canaris, beleuchtet seine wissenschaftlichen Erfolge und widmet sich sodann der Vertrauenshaftung in ihren einzelnen Bestandteilen. Diese soll insbesondere der Vertragshaftung gegenübergestellt werden. Im Anschluss folgt eine Darstellung der Rezeption in der Literatur und Rechtsprechung im In- und Ausland
The DEEP2 Galaxy Redshift Survey: Mean Ages and Metallicities of Red Field Galaxies at z ~ 0.9 from Stacked Keck/DEIMOS Spectra
As part of the DEEP2 galaxy redshift survey, we analyze absorption line
strengths in stacked Keck/DEIMOS spectra of red field galaxies with weak to no
emission lines, at redshifts 0.7 <= z <= 1. Comparison with models of stellar
population synthesis shows that red galaxies at z ~ 0.9 have mean
luminosity-weighted ages of the order of only 1 Gyr and at least solar
metallicities. This result cannot be reconciled with a scenario where all stars
evolved passively after forming at very high z. Rather, a significant fraction
of stars can be no more than 1 Gyr old, which means that star formation
continued to at least z ~ 1.2. Furthermore, a comparison of these distant
galaxies with a local SDSS sample, using stellar populations synthesis models,
shows that the drop in the equivalent width of Hdelta from z ~ 0.9 to 0.1 is
less than predicted by passively evolving models. This admits of two
interpretations: either each individual galaxy experiences continuing low-level
star formation, or the red-sequence galaxy population from z ~ 0.9 to 0.1 is
continually being added to by new galaxies with younger stars.Comment: A few typos were corrected and numbers in Table 1 were revise
Dependence of Galaxy Quenching on Halo Mass and Distance from its Centre
We study the dependence of star-formation quenching on galaxy mass and
environment, in the SDSS (z~0.1) and the AEGIS (z~1). It is crucial that we
define quenching by low star-formation rate rather than by red colour, given
that one third of the red galaxies are star forming. We address stellar mass
M*, halo mass Mh, density over the nearest N neighbours deltaN, and distance to
the halo centre D. The fraction of quenched galaxies appears more strongly
correlated with Mh at fixed M* than with M* at fixed Mh, while for satellites
quenching also depends on D. We present the M*-Mh relation for centrals at z~1.
At z~1, the dependence of quenching on M* at fixed Mh is somewhat more
pronounced than at z~0, but the quenched fraction is low (10%) and the haloes
are less massive. For satellites, M*-dependent quenching is noticeable at high
D, suggesting a quenching dependence on sub-halo mass for recently captured
satellites. At small D, where satellites likely fell in more than a few Gyr
ago, quenching strongly depends on Mh, and not on M*. The Mh-dependence of
quenching is consistent with theoretical wisdom where virial shock heating in
massive haloes shuts down accretion and triggers ram-pressure stripping,
causing quenching. The interpretation of deltaN is complicated by the fact that
it depends on the number of observed group members compared to N, motivating
the use of D as a better measure of local environment.Comment: 23 pages, 13 figures, accepted by MNRA
An Actin-Based Wave Generator Organizes Cell Motility
Although many of the regulators of actin assembly are known, we do not understand how these components act together to organize cell shape and movement. To address this question, we analyzed the spatial dynamics of a key actin regulator—the Scar/WAVE complex—which plays an important role in regulating cell shape in both metazoans and plants. We have recently discovered that the Hem-1/Nap1 component of the Scar/WAVE complex localizes to propagating waves that appear to organize the leading edge of a motile immune cell, the human neutrophil. Actin is both an output and input to the Scar/WAVE complex: the complex stimulates actin assembly, and actin polymer is also required to remove the complex from the membrane. These reciprocal interactions appear to generate propagated waves of actin nucleation that exhibit many of the properties of morphogenesis in motile cells, such as the ability of cells to flow around barriers and the intricate spatial organization of protrusion at the leading edge. We propose that cell motility results from the collective behavior of multiple self-organizing waves
The DEEP3 Galaxy Redshift Survey: The Impact of Environment on the Size Evolution of Massive Early-type Galaxies at Intermediate Redshift
Using data drawn from the DEEP2 and DEEP3 Galaxy Redshift Surveys, we
investigate the relationship between the environment and the structure of
galaxies residing on the red sequence at intermediate redshift. Within the
massive (10 < log(M*/Msun) < 11) early-type population at 0.4 < z <1.2, we find
a significant correlation between local galaxy overdensity (or environment) and
galaxy size, such that early-type systems in higher-density regions tend to
have larger effective radii (by ~0.5 kpc or 25% larger) than their counterparts
of equal stellar mass and Sersic index in lower-density environments. This
observed size-density relation is consistent with a model of galaxy formation
in which the evolution of early-type systems at z < 2 is accelerated in
high-density environments such as groups and clusters and in which dry, minor
mergers (versus mechanisms such as quasar feedback) play a central role in the
structural evolution of the massive, early-type galaxy population.Comment: 11 pages, 5 figures, 2 tables; resubmitted to MNRAS after addressing
referee's comments (originally submitted to journal on August 16, 2011
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