521 research outputs found
Going Home after Hurricane Katrina: Determinants of Return Migration and Changes in Affected Areas
This paper examines the decision of Hurricane Katrina evacuees to return to their pre- Katrina areas and documents how the composition of the Katrina-affected region changed over time. Using data from the Current Population Survey, we show that an evacueeâs age and the severity of damage in an evacueeâs county of origin are important determinants of whether an evacuee returned during the first year after the storm. Blacks were less likely to return than whites, but this difference is primarily related to the geographical pattern of storm damage rather than to race per se. The difference between the composition of evacuees who returned and the composition of evacuees who did not return is the primary force behind changes in the composition of the affected areas in the first two years after the storm. Katrina is associated with substantial shifts in the racial composition of the affected areas (namely a decrease in the percentage of residents who are black) and an increasing presence of Hispanics. Katrina is also associated with an increase in the percentage of older residents, a decrease in the percentage of residents with low income/education, and an increase in the percentage of residents with high income/education.Hurricane Katrina; Geographic Mobility; Return Migration; Disasters
Test of CPT Symmetry and Quantum Mechanics with Experimental data from CPLEAR
We use fits to recent published CPLEAR data on neutral kaon decays to
and to constrain the CPT--violation parameters
appearing in a formulation of the neutral kaon system as an open
quantum-mechanical system. The obtained upper limits of the CPT--violation
parameters are approaching the range suggested by certain ideas concerning
quantum gravity.Comment: 9 pages of uuencoded postscript (includes 3 figures
Tests of the Equivalence Principle with Neutral Kaons
We test the Principle of Equivalence for particles and antiparticles, using
CPLEAR data on tagged K0 and K0bar decays into pi^+ pi^-. For the first time,
we search for possible annual, monthly and diurnal modulations of the
observables |eta_{+-}| and phi_{+-}, that could be correlated with variations
in astrophysical potentials. Within the accuracy of CPLEAR, the measured values
of |eta_{+-}| and phi_{+-} are found not to be correlated with changes of the
gravitational potential. We analyze data assuming effective scalar, vector and
tensor interactions, and we conclude that the Principle of Equivalence between
particles and antiparticles holds to a level of 6.5, 4.3 and 1.8 x 10^{-9},
respectively, for scalar, vector and tensor potentials originating from the Sun
with a range much greater than the distance Earth-Sun. We also study
energy-dependent effects that might arise from vector or tensor interactions.
Finally, we compile upper limits on the gravitational coupling difference
between K0 and K0bar as a function of the scalar, vector and tensor interaction
range.Comment: 15 pages latex 2e, five figures, one style file (cernart.csl)
incorporate
New insights into the photochemistry of carotenoid spheroidenone in light-harvesting complex 2 from the purple bacterium Rhodobacter sphaeroides
Light-harvesting complex 2 (LH2) from the
semi-aerobically grown purple phototrophic bacterium
Rhodobacter sphaeroides was studied using optical (static
and time-resolved) and resonance Raman spectroscopies.
This antenna complex comprises bacteriochlorophyll
(BChl) a and the carotenoid spheroidenone, a ketolated
derivative of spheroidene. The results indicate that the
spheroidenone-LH2 complex contains two spectral forms
of the carotenoid: (1) a minor, ââblueââ form with an S2
(11
Bu
?) spectral origin band at 522 nm, shifted from the
position in organic media simply by the high polarizability
of the binding site, and (2) the major, ââredââ form with the
origin band at 562 nm that is associated with a pool of
pigments that more strongly interact with protein residues,
most likely via hydrogen bonding. Application of targeted
modeling of excited-state decay pathways after carotenoid
excitation suggests that the high (92%) carotenoid-to-BChl
energy transfer efficiency in this LH2 system, relative to
LH2 complexes binding carotenoids with comparable
double-bond conjugation lengths, derives mainly from
resonance energy transfer from spheroidenone S2 (11
Bu
?)
state to BChl a via the Qx state of the latter, accounting for
60% of the total transfer. The elevated S2 (11
Bu
?) ? Qx
transfer efficiency is apparently associated with substantially
decreased energy gap (increased spectral overlap)
between the virtual S2 (11
Bu
?) ? S0 (11
Ag
-) carotenoid
emission and Qx absorption of BChl a. This reduced
energetic gap is the ultimate consequence of strong carotenoidâprotein
interactions, including the inferred hydrogen
bondin
What Do We Know About Contracting Out in the United States? Evidence from Household and Establishment Surveys
A variety of evidence points to significant growth in domestic contracting out over the last two decades, yet the phenomenon is not well documented. In this paper, we pull together data from various sources to shed light on the extent of and trends in domestic outsourcing, the occupations in which it has grown, and the industries engaging in outsourcing for the employment services sector, which has been a particularly important area of domestic outsourcing. In addition, we examine evidence of contracting out of selected occupations to other sectors. We point to many gaps in our knowledge on trends in domestic outsourcing and its implications for employment patterns and to inconsistencies across data sets in the information that is available. We recommend steps to improve data in this area
Development and validation of a short version of the Partnership Self-Assessment Tool (PSAT) among professionals in Dutch disease-management partnerships
Background: The extent to which partnership synergy is created within quality improvement programmes in the Netherlands is unknown. In this article, we describe the psychometric testing of the Partnership Self-Assessment Tool (PSAT) among professionals in twenty-two disease-management partnerships participating in quality improvement projects focused on chronic care in the Netherlands. Our objectives are to validate the PSAT in the Netherlands and to reduce the number of items of the original PSAT while maintaining validity and reliability. Methods. The Dutch version of the PSAT was tested in twenty-two disease-management partnerships with 218 professionals. We tested the instrument by means of structural equation modelling, and examined its validity and reliability. Results: After eliminating 14 items, the confirmatory factor analyses revealed good indices of fit with the resulting 15-item PSAT-Short version (PSAT-S). Internal consistency as represented by Cronbach's alpha ranged from acceptable (0.75) for the 'efficiency' subscale to excellent for the 'leadership' subscale (0.87). Convergent validity was provided with high correlations of the partnership dimensions and partnership synergy (ranged from 0.512 to 0.609) and high correlations with chronic illness care (ranged from 0.447 to 0.329). Conclusion: The psychometric properties and convergent validity of the PSAT-S were satisfactory rendering it a valid and reliable instrument for assessing partnership syne
Job Flows, Demographics and the Great Recession
The recession the United States economy entered in December of 2007 is considered to be the most severe downturn the country has experienced since the Great Depression. The unemployment rate reached as high as 10.1 percent in October 2009 - the highest we have seen since the 1982 recession. In this paper we examine the severity of this recession compared to those in the past by examining worker flows into and out of unemployment taking into account changes in the demographic structure of the population. We identify the most vulnerable groups of this recession by dissagregating the workforce by age, gender and race. We find that adjusting for the aging of the U.S. labor force increases the severity of this recession. Our results indicate that the increase in the unemployment rate is driven to a larger extent by the lack of hiring (low outflows), but flows into unemployment are still important for understanding unemployment rate dynamics (they are not as acyclical as some literature suggests) and differences in unemployment rates across demographic groups. We find that this is indeed a mancession, as men face higher job separation probabilities, lower job finding probabilities and, as a result, higher unemployment rates than women. Lastly, there is some evidence that blacks suffered more than whites (again, this difference is particularly pronounced for men)
Dispersion relation analysis of the neutral kaon regeneration amplitude in carbon
We apply a forward dispersion relation to the regeneration amplitude for kaon scattering on \PCtw using all available data. The CPLEAR data at low energies allow the determination of the net contribution from the subthreshold region which turns out to be much smaller than earlier evaluations, solving a long standing puzzle
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