Female labor supply and child care

We use household income tax data to estimate a structural model of female labor supply and utilization of paid child care outside the home. We find that child care costs have little impact on the participation decision of mothers of young children. However, they influence hours of work, as well as the decision to utilize paid child care. We use our results to simulate various policy reforms. Suppressing the APE (Parental Education Aid) would cause the participation rate in our sample to rise by 4 points and the proportion of mothers using outside paid care to rise by 2 points. Examining the effects on aggregate female labor supply of other policies that affect child care costs, we generally find that intensive effects caused by changes in working time are of the same order of magnitude as extensive effects due to changes in female participation.Child Care, female labor supply, fiscal policies

Coherent state triplets and their inner products

It is shown that if H is a Hilbert space for a representation of a group G, then there are triplets of spaces F_H, H, F^H, in which F^H is a space of coherent state or vector coherent state wave functions and F_H is its dual relative to a conveniently defined measure. It is shown also that there is a sequence of maps F_H -> H -> F^H which facilitates the construction of the corresponding inner products. After completion if necessary, the F_H, H, and F^H, become isomorphic Hilbert spaces. It is shown that the inner product for H is often easier to evaluate in F_H than F^H. Thus, we obtain integral expressions for the inner products of coherent state and vector coherent state representations. These expressions are equivalent to the algebraic expressions of K-matrix theory, but they are frequently more efficient to apply. The construction is illustrated by many examples.Comment: 33 pages, RevTex (Latex2.09) This paper is withdrawn because it contained errors that are being correcte

Etude de la répartition des tsé tsé (Diptera : Glossinidae) en zone de savane humide (République Centrafricaine) : évaluation de techniques de prospection entomologique

Two trapping methods were compared during a survey of the distribution of tsetse flies in the Mbororo cattle breeding area of the Central African Republic : (a) several traps dispersed throughout the reverine forest galleries and remaining only one day at each site; (b) one sentinel trap placed at the cattle drinking point and remaining for several days. The latter method was more reliable and is therefore recommended. The concentration of tsetse flies at the drinking points was negligible during the rainy season. (Résumé d'auteur

Mechanical behavior of recrystallized Zircaloy-4 under monotonic loading at room temperature: Tests and simplified anisotropic modeling

Mechanical behavior of recrystallized Zircaloy-4 was studied at room temperature in the rolling-transverse plane of a thin sheet. Uniaxial constant elongation rate tests (CERTs) were performed along with creep tests, over a wide range of strain rates. Based on a simplified formulation, different sets of parameters for an anisotropic viscoplastic model were found to fit the stress–strain curves. Notched specimen tensile tests were carried out with a digital image correlation (DIC) technique in order to determine the strain field evolution. From these measurements and the determination of Lankford coefficients, the most consistent model was selected and simulated data were successfully compared with the experimental observations

The coupling of valence shell and particle-hole degrees of freedom in a partial random phase approximation

It is well known that the random phase approximation breaks down in the absence of a substantial energy gap between occupied and unoccupied single-particle states. Particle-hole excitations are then inevitably accompanied by substantial rearrangements of the particles in the neighbourhood of the Fermi surface. To accommodate this situation, a partial RPA is introduced which corresponds to replacing only the particle-hole degrees of freedom by bosons but leaving the valence space degrees of freedom intact. The PRPA is therefore a mapping of the many-fermion dynamics into the dynamics of a coupled boson-valence space. In application of the PRPA, algebraic methods, of either a fermionic or Lie algebra type, can be introduced, if desired, to facilitate the treatment of the valence space degrees of freedom. Results of applications are presented in which the valence space particles are treated in the rotational and SU(3) models, and are coupled strongly to giant dipole and quadrupole resonances.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26774/1/0000326.pd

New perspective on the U(n) Wigner-Racah calculus. I. Vector coherent state theory and construction of Gel'fand bases

Using a vector coherent state theory, it is shown that the construction of Gel'fand bases for the unitary group is particularly simple. The very specific rules for construction of the states greatly facilitate the subsequent computation of matrix elements of the generators of the u(n) Lie algebra.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48816/2/jav20i9p2241.pd

Canonical orthonormal Wigner supermultiplet basis

The explicit construction of an orthonormal basis for states of good spin, isospin and SU(4) Wigner supermultiplet symmetry is given in a Bargmann representation space. A complete set of quantum labels is provided by a Sp(3, R) contains/implies U(3) complementary symmetry.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48815/2/jav20i2p257.pd

Low Energy States of 3181Ga50^{81}_{31} Ga_{50} : Elements on the Doubly-Magic Nature of 78^{78}Ni

Excited levels were attributed to $^{81}_{31}$Ga$_{50}$ for the first time which were fed in the $\beta$-decay of its mother nucleus $^{81}$Zn produced in the fission of $^{nat}$U using the ISOL technique. We show that the structure of this nucleus is consistent with that of the less exotic proton-deficient N=50 isotones within the assumption of strong proton Z=28 and neutron N=50 effective shell effects.Comment: 4 pages, REVTeX 4, 5 figures (eps format

Distribution of trace elements in waters and sediments of the Seversky Donets transboundary watershed (Kharkiv region, Eastern Ukraine)

International audienceThis paper reports on the aquatic chemistry of trace elements in terms of spatial and temporal distribution, but also pollution sources in the transboundary watershed of the Seversky Donets River (Ukraine/Russia). Bed sediments and filtered water were collected from the Udy and Lopan Rivers at sites from the river source in the Belgorod region (Russia) to rural and urban areas in the Kharkiv region (Ukraine) in May and August 2009. Priority trace elements (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn), an urban tracer (Ag) and additional metals (Co, Mo, V) and Th were measured in stream water and sediments. The low levels and variability of Th-normalized concentrations indicated the absence of geochemical anomalies in the upstream part of the rivers and suggested that these data represent a regional baseline for trace elements in bed sediments. In contrast, water and sediments within the city of Kharkiv were contaminated by Ag, Pb, Cd, Cu, Cr and Zn, which are mainly attributed to municipal wastewater inputs and urban run-off. Results of the environmental quality assessment showed that element concentrations in the sediments can be considered as potentially toxic to aquatic organisms in sites downstream of the wastewater discharges